Yes, the 500 will work fine, but, he hasn't commented on what he really plans, or how he wants to drive it. With not knowing, I figure it as what if ?
Vacuum secondaries, and that 4 barrel will still be very good, unless he puts his foot in it. I wouldn't want to see him go lean on the top end. I'm just talking ingeneral here guys. I like to make sure I have that extra punch if I need it. I run a little 390 cfm on my 2.8. Get good mileage, but have the punch when I need it. And the engine can only draw so much depending on cubic inches anyway.

A belated Happy 78th Birthday Roger Spears
Belated Happy Birthday