408 build up
Get all the parts and machining completed- and then phone Jim @ Racer Brown and get yourself a custom ground cam based on your final combination - not a catalogue. you won't be disappointed.
3.23 gears might be a tad hight in ratio - go for a set of 3.55s or 3.91s depending on tire dia. suggest targeting for 2600rpm @ 60mph so your in the good torque band of the cam and ultimately the engine.
If you plan on a lot of ftreet driving, I'd go with the RPM performer - but not the Airgap - cooler weather plays havic with warmup and idle quality.
make sure you have the amount of initial advance in the 14-18* range no matter what cam you go with. My experience SBM like as much initial as you can give it and still start.
I'll leave the carb selection up to you - I would go with a 650dp Speed Demon as long as the cam duration @50 stays below 240* or a Holley 3310vs.
Most important - have fun.
Kepp us updated as you progress.