Get a 400 block or Motor,(use the 350 crank if you want) 60lb oil pump w/harden shaft, stock 4bb or Performer RPM intake with a Cliff Ruggles Q-jet, and a Dave's Small body HEI. Alway go with one of the aftermarket rods. Have the 350 heads gone through or even ported and use RA long branch manifolds from RARE. Get some roller lifters to top it off. Maybe a S grind cam?? Or get one of the 428 stroker kits for a 400 block with all the above mentioned parts.
If you can find a good machine shop up their have them get the parts you need from The Pontiac DUDE or Butler or someone else you can trust. I think this would give you the reliability and power you are looking for. If its not enough then you only need to throw in a bigger cam. Again my .02
