I spent a little time in the shop today getting acquainted with the factory A/C setups...well, one of the three I have, anyway...since I've decided to go ahead and use the factory setup for my project rather than a dealer-installed add-on unit. I have three units, two of which have cracked cases, and another with very minor case damage. The two with bad cases would be my parts units. I decided to go ahead and tear down the worst of the three to educate myself with how they were assembled and how to properly disassemble them. I figured that I'd probably end of breaking something during disassembly, so I'd prefer it be on a parts unit rather than the good one, so I grabbed the worst of the three and did a full teardown. I'm in the process of putting together a project update page with a bunch of pics of the teardown, to be posted soon.
Anyway, I was intrigued to find that all three units I have are just a little bit different. While they all appear to have the same case, the front aluminum trim panels and front registers are different. Here's a comparison photo I just finished editing:
You'll see that the '68 doesn't have the familiar woodgrain trim panel across the front, and from what I've found doing a little research, it's typical of a '68-'69 unit. The '70-'72 units used the woodgrain trim.
However, the front registers are also different on the two '70-'72 units. The middle unit in the pic above uses the '68-'69 registers, while the third unit pictured above uses a completely different style of register, although the two register styles are dimensionally identical. So until I hear differently I'm going to make an assumption that the '70 units were a one-year-only item, which used the old '68-'69 style registers and the new woodgrain panel, and that the front registers were updated for the '71-'72 units.
I'd appreciate for any of you who have these factory A/C units to take a close look at yours and compare them to the pictures above and let me know how they compare. I'd like to semi-verify that my assumptions are correct.
