[FUNFER2]

Mark- Your getting it !
It sound like a mild built engine is for you. Check out the crate engines from Ford. The 460 is a good motor for the price. I like the idea of the 514 cu.in. over 600 HP with a warranty and under 9 K, that's a great engine package. A basically stock FE is also a good choice. You could have one with a mild cam, less than 10:3:1 compression steel head, single carb or throttle body injection, MSD ignition, Edelbrock RPM intake, ect...., 450 HP for around 5K.
Buying aluminum heads is a up grade. You can spend a lot......of money on heads but, it's a great way of gaining HP. Make sure you buy good roller rockers, rocker shafts with end stands and good springs. With a cam, stay under 600 lift, the higher you go you'll need dual valve springs, stronger push rods ect... If you like a engine to rumble, go with a higher over lap and duration, lower lift. With these type's of engines, you'll be very happy with the performance & longevity.

Thanks,