I've got the pictures and everything to do a writeup on the differences between a T-19 and a ZF5 (to do an article on the swap I did last summer)...maybe this'll be the impetus for me to get off my tail and get it done.
I don't believe the floorpan changed between '80 and '97, but I could be mistaken. Certainly, a floor pan insert from a '87-'91 truck will fit an '80-'86 truck; the ZF pan insert I have in my truck came out of an '89, and other than cutting a hole for the transfer case gearshift lever ('87+ trucks have the lever coming out of the lower floor pan, while '80-'86 trucks have the lever coming out of the pan insert), it fit in perfectly with no modification whatsoever.
However, unless the 2WD pan is different (unlikely), an unmodified T-19 pan will not fit around a ZF5. Take a look at the pictures I attached to this post, but with how the T-19's pan is shaped, the pan will come into contact with the top of the ZF tranny with about 3/4" (EWAG) left to go before the insert comes into contact with the top of the tranny. You might be able to modify the T-19 pan with a BFH to make clearances work, but you have to be careful about deforming the pan to the point where bolting it down will be a PITA.
I've never seen the pan insert from a truck with an auto tranny, but I know the slushboxes are bigger...maybe the E4DOA pan will fit around the ZF? Then, all you would need to do is cut a hole for the lever and drill holes to mount the boot onto.
BTW, the first pic was taken while the T-19 was still in the truck. The T-19 pan insert is in place, and the ZF pan is sitting to the left of it. The second pic is what the ZF looks like without a pan at all in place. The third pic shows how the T-19 pan "fits" around the ZF5...you can see how much of a gap there is, and the pan is sitting on the tranny.
Hope this helps some...good luck!
