I have decided to build a BB for my 86gt t top car. Looking to make a little over 500hp. I cam across a 429 thunder jet that has been rebuilt and aluminum intake and a bigger cam. That guy is asking $1,200 I haven’t seen it in person yet but after doing a little looking I am not sure that is worth doing for what I want. Would I be better off building a 460? The car has subframe connectors jack rails stiffer cros bracing and will have a 6pt cage. Rear is mini tubed with a 9”. Thanks for any input.