[Troyport]

Thanks for the reply, sorry I was not clear. I have a stock 351 V6, stock exhaust manifolds (manifolds are NOT shaped like an I-beam) The exit of the manifolds point straight down, dumping out of the center (which I am pretty sure is the way all the manifolds point for the V6's. It looks like the pipes are attached with a flat gasket, and not a donut-style gasket, but I am not sure. I want a left and right pipe leading from these manifolds that terminate in a normal spot under the truck, facing towards the back, 2.5" diameter. Then I can add my own intermediate pipes, mufflers, etc.
It has dual exhaust now, but it is getting very rusty. And it looks like someone hacked-up a Y-pipe to do what I want to do, the welding is just hideous. I am not much of a welder, so my hope is to get proper downpipes then build from there with sleeve-style clamps. The truck is a 1968, so not even sure if what may fit a 60 - 66 would even work on my truck, but no one else has been able to help me, it seems like most people either have or swap in V8's. It is very functional now, so I don't want to pull it apart without a clear path forward. Thanks again.