Ram Horns, mufflers and rest of exhaust

[MASTERBrian]

I'm looking to finally get to the exhaust on my 1960 Suburban with an approx 330HP SBC 350. I have the stock torsion front end, but she's been lowered 2-1/2" with spindles and about the same with the torsions. 4" HD springs in the rear. This cause some issue with the tail pipe hitting a brake line, so I cut the pipe off until I could get the exhaust replaced, but now it's apparently causing my fuel line to vapor lock. Needless to say, it's time to get moving forward on the exhaust...

I currently have a 2" center dump Ram Horn on the passenger side, but the driver side is a rear dump truck manifold. This begs can I do a center dump on the driver side? Then can I easily step up to a 2-1/2" collector size? I'm thinking I want to run 2-1/4" exhaust pipes to get a little more flow.

Next, I'm trying to decide on a muffler for her. Currently, I have a 6" diameter 20" long set of mufflers. It is dual exhaust and I want to keep that, with the addition of H pipe. I don't want the exhaust to be over bearing when inside, but I do want to here the cam and have a nice hot rod V8 sound.

I've been looking at the Flowmaster HP2. FM says they are fairly mellow inside, have an insulating cover, which might be good against the plywood floor. The problem is the muffler shop says they are just a glorified glasspack that is over priced....they sell Flowmaster and Magna flow. Any other good suggestions? I don't want some huge oval muffler that has to be set sideways in the X frame causing it to hang down and be a possible catch point.

Also, Summit sells their steel 2-1/2" ram horns for $139 or the Flotech cast ram horns for $207.