Need to find information on after market products.

what are you looking for? there are a shitload of aftermarket performance parts for 4.3L's

there are factory performance applications of 4.3's such as the typhoon and cyclone

We'll be updating the RockHer II build thread after we get back from Vegas, including info on our new race-built vortec v-6 that James Schofield built. He used to work at BTF, now works for Valvoline Drag Racing, building their Top Alcohol Funny Car engines.
We're building some SERIOUS power on an engine that uses the stock MPI intake and fuel injection.

The link to that thread is in my signature and there's already some info on the vortec there.

there are quite a few parts on the summit website for 4.3's