You may be able to "backfeed" a two-pole breaker at your sub-panel. That is, you ignore the two hot lugs and connect the two hot wires to the "pseudo-main" breaker (my term) so that the incoming current goes through the breaker "backwards" to the hot busses. HOWEVER, to do this legally, you'll need a hold-down kit for the backfed breaker to prevent someone from pulling out an energized breaker accidentally or ignorantly. I have no idea whether a hold-down kit is available for that particular panel. Another possible low-cost workaround is to install a cheap disconnect ahead of the panel. 30- 60- and/or 70-amp disconnects (often marketed as air conditioning disconnects) can be purchased at big box stores for as low as about $10. Because you're planning to put a six-slot panel in a separate building, you'll also need to drive at least one (and probably two) grounding electrode(s) to be connected to the panel ground bar with #6 (or larger) copper wire. Since you seem pretty certain that you'll never need more than those two circuits, it might be worth pointing out that you may have another available option. That is, you could run a single 20-amp circuit to the shed and skip having a sub-panel (as well as local ground rods) altogether. In this context, the definition of "single circuit" includes what is known as a "multiwire branch circuit" (MWBC) having two hots and a shared neutral. An MWBC can then be split into what amounts to two circuits at the shed. So, if you size both of the circuits in the shed at 20 amps, you can use one hot for your receptacles and the other for your lights, sharing the single neutral. Of course, your lighting circuit will have to be wired with #12 wire (whereas #14 would be OK for the lights if it were a 15-amp circuit) but that would probably not add anything to the costs because, as often as not, you save money by using one wire size. The obvious disadvantage of running an MWBC without a subpanel is that if you exceed the overcurrent limit on either your lighting or your receptacles, they'll both trip simultaneously and you'll have to walk back to the house to reset. (The breaker in your main panel must be a double breaker with the hots on opposite poles -- never two independent breakers!) If you want to investigate this second option, be sure to run it by your local AHJ (inspector or permit-issuing office) first. Based on a couple of anecdotal accounts I've read on this forum, some local codes do not permit the MWBC approach. YMMV.

As I think of it, the size of the disconnect isn't an issue because if there's a problem the breaker in the sub-panel would trip. Any you're correct the dude isn't an electrician, but he's going to school and knows just enough to be danger-ous . Nonetheless, he's who the AC installers use, so I figured I'd better use his advice. He also told me that I needed to use a different wire to the unit from the disconnect and that it needed to be in a flexible shield. That wasn't a problem because I had the wire and they'll furnish the shield. Folks down in this neck of the woods can't always seem to get things right. Bob'll say something and then Ray'll say something else. But they got themselves a varmit that demands and will get what he has coming one way or another. The guy that gave the estimate, for example, promised to add an additional vent in the dinning room, which had been added on since original construction (just having air added to an existing central heat system). His work partner said they couldn't do it (and gave a good, understandable reason), but I told him there "ain't no such word as "cain't"; to "find" a way to do it! They have to finish today, so we'll see. I have an idea or so myself.

Hi ronnatalie, Thank you very much for your reply, and thank you for providing correct terminology (this should make it easier to communicate). This time around I have included an amazingly life like sketch of my panel that should also help out with the communication. Following your response I have a couple of questions: 1) Now that I have disconnected the two long strips from each other (let's call them ground bar and the neutral bar), do I need to unscrew the ground bar from the service panel case (as you can see from the picture it is connected with a screw). I guess my question is, should any of the bars in the service panel (main lug/sub panel) be connected to the case of said panel? 2) The two short strips on the side of the longer bars, are they pre-installed ground strips/bars? 3) The cable connecting the service disconnect and the main lug is currently (AFAI tell) comprised of only three wires (2 hot + neutral). Do i need to have a fourth wire for ground between the service disconnect and the main lug? 4) I went with Siemens because it had a package in the orange store that included a large number of breakers, most notably single pole 20A that would fit nice in my kitchen. I was disappointed that all the breakers provided were 'full size' and not 'space savers' (I think these might be called tandem, but correct me if I'm wrong). Do you think that returning the set and going with Square D would be a better choice and just buying 'tandem' breakers separately (didn't notice any company's bundle offering 'tandem' breakers in their set) to save on the space inside the panel? Thank you for taking time to look and (hopefully) answer these questions.

If you needed 30 inches to anything that would mean 60 inches of working clearance. You are only required 30 inches. The disco does not have to be centered on the 30 inches either. It can be right to the edge of the unit, as long as there is 30 inches off to the side. There are differing opinions on whether working clearances apply to AC disco's. Some AHJ's don't consider them to be "likely to be serviced while energized", exempting them from the working clearance requirements, while some do.