I suggest going 100% with the ISC setup. Carb, distributor, engine, suspension, exhaust, etc. Mike's parts fit and work and are very strong. I have have had his 3rd arm setup for 5 years without a problem. I personally have many of his parts on my car except I do have the SDJ header with 3" over the axle and it seems to do very well in the power category but I can't say if it is superior to the ISC header. I have the Dynomax Ultra 17296 3" muffler (NAPA) and have never had a sound problem. Hang the exhaust with chain.