He can get away with the 30lbers for 400-425 hp using stock fuel pressure, I'd say a 36,39, or 42 would be better in the long run depending but you would have to log injector duty cycle.
Why the old school V-belts?? How is the MAF setup now?? Any more recent pics?? If you run it with no filter on the MAF it will run like crap. Try changing the clocking of the MAF too.
at .050 what is it, the advertised doesn't help much..
but regardless it will need a tune...it may be "mild" for a 351w but with the stock computer it is not