new 360 advise needed please.

Regular gas is no problem with a "74" 360. I'd put some stainless steel valves in the J heads, clean up the bowls, and run the 340 cam and springs. Try a TQ and run the 3.23 gears, that is close to all the small block performance engines came with. We used to cruise all day at 100 mph with those gears. Should be a bullet proof combination.