318 cam selection

I am building a 318 for my 72 W100 Powerwagon. I need some help picking a cam. Heres the build as of right now:

1971 std. bore block
stock crank, rods, and piston
Melling HV oil pump
Cloyles double roller timing chain
#302 casting heads
Edelbrock performer intake
Holley 600 cfm carb.
Headers w/ 2 1/4" dual exhaust w/ flowmaster super 40's

Also my truck has a 4 spd. manual trans. and 3.91 gears. What would be the best cam for my application???