No issue with the use of the PHS, my brother had it posted on PY to try to stir up more information on these cars.
Thus far, have found 2 1968 Comanche Firebirds of the 13 built and 3 1969 Comanches (including mine). The 69's are two convertibles and one hardtop. My convertible is the only manual transmission (M21) or L74 engine.
I don't have the original window sticker. I am still trying to locate the original owner who apparently still lives in Montreal but no luck yet.
Will send you some Comanche literature that I have collected.