Another AC Problem

[dagObx]

So, after my wreck last fall I installed new condensor, drier, aux. fan, fan clutch (from a 602, used old fan [cheap]), new radiator. Flushed AC system per instructions found here, put in mineral oil in proper amount, pulled vacuum (not necessarily in this order) & popped in the proper amount of R-12 (re-convert from 134a). On edit: This is a '87 300DT.

The AC never cooled the car very well - lowest temps on 134a were around 60*F, even after a tech went over the system. The wreck took all that out, which was why I went with R-12.

Now, even with the R-12 the lowest temps from the vents are around 60*F. A home HVAC buddy of mine suggests that it might be the expansion valve needs changing. Does this sound like a possibility? All other parts except compressor are new. Advice/tips? Hate to tear into dash without some guidance.