The question of running about the same car makes sense to a point.
Would any of you agree you could take a 1965 273 4bb Commando and put it in a totally race preped 2021 NHRA 'Pro Stock' car and beat any 100% factory stock 1968-71 340 Duster?
Might even do it with Richard Holdner's or UT's \6. Nah...
Both cars ready to run but NO ENGINE, just the body with trans... So if both cars are even preped, no 4.88 gears in one and 2.94's in the other, just say like 3.23/3.54 or 3.91/4.10's differences. Stock type trans, no Linco 20 speeds with air shift, so a 904/727 or 883. No long ladder bar or $$$ 4 link's, slapper bars or Caltrak's are OK.
Now given the $3000, pick a 318 or a 340, NOTHING ELSE. Then you must BUY all parts, new or used, including paint, nuts and bolts or a running core if you want. No FREE'bs, everything paid for at fair market. No W2's or tunnel ram from the back of the garage.
How hard is this to understand?