I had a painfull discovery while installing the dash. I had it all in and was connecting the crotch cooler pipe, when it seems the pipe does not fit the left drivers vent ducting...wtf!! The 1988 dash is different from the 1991 dash in one way...the left ducts are different. I had to pull the dash back out 5 inches to remove the duct and install the 1991 duct. See below for the difference.
Left is 1991-Right is 1988 left side dash vent duct.
The good news is I'm done.
Here is what I upgraded-
I installed a new heater core, refinished my steering wheel cover, added a carbon fibre style overlay to my gauges, added polished alum. gauge bezels, covered the dash in black Alcantara, new leather seat covers, all door cards recovered in leather, put in a new power antenna, added 6 new speakers to replace old rotting ones, added seat heaters to both front seats, added a c's short shifter, made a new panel for the seat heater switches, new leather armrest cover, shift boot and e-brake cover...whew.
cwd