your block is a 71,D=70s. the timing set to use is a multi key way, as the 429/460 used a retarded gear set to meet emissions.. I would use a flat tappet cam myself .several yrs ago HRMagazine had a real good artical on building the 460. made 500 hp. I had a similiar eng in a van, less cam, and used it for towing. it went 9.30 ,in the 1/8 mi, 6000 lbs with a 600 holley and the stock intake. very durable eng.