If you have to remove 4 tiles to get to the valve, then you're removing far more of the surface waterproofing than I'm comfortable with. Especially if this was done with a modern vapor barrier in place or membrane. I'd MUCH prefer to go through the rear and affect the watertight integrity of the shower as little as possible. I don't know what brand of valve you picked, but pick the best quality that you can for this second go around.

Aside from the expense of glass and the drilling into my new tile or whatever, I'm also not convinced I would keep up with the doors as well as I'd like. Or, even if I did, that the 'used' version during the week wouldn't just get to me in my beautiful new bathroom -- as pretty and spacious as it would feel with glass. So, my choice was to go with a beautiful shower curtain first and see how I like it overall in there. (My new tub comes out a bit more than the last one, not much, but it was too darn expensive to move the toilet over and just not worth it). So, my advice would be to do a mock up a curtain and see if you like the looks. If so, give it an inexpensive go! before plunging into a new door. If you don't like having or maintaining the one you have now, you'll likely feel the same with a new one, too.

Our 4 yr old Delta (model# 132900 ) works as you describe. It is stamped "Delta" on the trim plate and the handle, and the trim plate screw holes are at 1:00 and 7:00 (actually closer to 2:00 and 8:00, but not quite.) Anyway, I would suggest taking both the trim plate and the handle off and take them with you to a big box store to match them up. The key is matching the holes on the trim plate, as well as the turning "stops" on the backside of the handle (so take the handle out of the package and look at the back of it closely). If they don't match, try a real plumbing supply, since the trim plate holes and stops can be different even for the same brands. This is how it is with Moen. Sometimes I buy a trim kit from a plumbing supply, other times the big box version, and sometimes I even have to parts from each place to freshen up a bathroom. (If I want a shiny new Moen tub spout, it's almost the same cost at my local plumbing supply to buy the entire trim kit vs. the spout by itself.) Good luck.

The text disappeared... Here again: My main shower is old and in need of updating. The shower is a single handle valve. The gold finish plate over the valve has a SA stamped on it which apparently stands for American Standard. At any rate, the valve works fine but I was wondering about update or upgrade options. Without tearing into the wall can I find the correct updated trim packages available today? I suppose I would have to tear into the wall to replace the valve? The existing main bath is entirely builders grade fixtures and I would like to upgrade but dont want to tear-out. What to do?