I'll try to keep this short.
I have:
a new '87+ 350 B2L Long block.
a complete parts engine '90 305 TBI
a recently bought '85-'88 TPI with the '86 and earlier distributor (the big one) and wire harness.

can I put both of those (1 or the other) distributors on my 350?
did both '86-earlier and '87-later have roller cams or just '87-later?
will my '87-later distributor plug right into my '86-earlier wire harness?

if both distributors are usable, wich would be better?
are the gears of the distributor direct inter-changeable?

 

I believe 87 and older may have had roller cams,but I do not see why you cannot use either distributer.Look at the gears and as long as they look the same thy should work.

 

well I read the gears on a distributor of a non-roller cam are not as hard, and if I were to use then on an engine with a roller cam, they'll strip shortly.