Hi there
I have a 27 chev 2 dr sedan like yours,i stayed with the original frame and used a speedway 4" dropped tube axle mounted on the original spring configuration.A reversed corvair box fits the frame well with little modification.I am running a 3.4 95 camaro v6 (60 degrees)so i dont need the side room for a small block or have to alter the firewall.If you plan on a fendered car this is an easy conversion.Don't discount the 6 cyl it can produce some nice hp and you have a little different car than everyone else.You can also use stock manifolds,2 lefts work well.My car handles well and the front end is nice and light,hope this helps cheers wayne