you can use the stock 6 cyl rear with a V8/auto combo as long as the V8 is relatively stock, and you dont use slicks, or otherwise stickey tires. best though to use an 8" rear and leave the six cyl rears to those of us who want to keep out six's and spank the V8's
you are right about the 302 swap in place of a 260. if he uses a tranny from the 302 then it is a bolt in swap. otherwise no.