I have 2 small cap HEI distributors (1103749 & 1103880) I was planning on using with my TPI swap. The block is an old 4 bolt 350 with a flat tappet cam. Can I use either of these be used safely without damaging the gears and waisting the engine? Thanks.

Yeah, either one will work fine. I think the problems come in when people use a stock distributor with an aftermarket roller cam.

I originally though that there was a difference between the newer and older distributers as well, but that isn't the case.

I do believe the difference is between roller and non-roller cammed engines. I've ran a 89 small cap HEI on a 73 block & cam for a while with no concerns

Thanks for the input!