The time has come... 440 freshen for B-body

My cousin has owned a '72 Polara with a 440 for a few years now and it has been a lot of fun getting it from a barely-running pig back to a proper running state. The car has 46,000 original miles, most of them garage-kept. The engine runs awesome; tons of torque and very smooth. Earlier this year my cousin bought a freshly-painted "roller" of a 1971 Satellite; original slant-6, 3-on-the-tree car with the intent of swapping in the 440 and a 4-speed. The car needs to be totally rebuilt as far as suspension and brakes go, and the interior is basically empty which my cousin is currently working on. This weekend I will drive up to his place which is an hour away and get my first look at the car in person; I have had to wait patiently many months as my cousin has been busy with more important stuff (SCHOOL).

I will be in charge of the engine and chassis work for the car and so far have a pretty good idea in mind of what to do with the engine. He already has lined up an 8 3/4" rear to swap in with cone-style sure grip and 3.55 gears. I am currently looking around Denver for good 4-speed trannies. We really want to put in a 4-speed as the car already came with a 3-speed manual so the conversion will be a lot easier than going from automatic but there are still a lot of things to consider. Anyway some more specifics on the engine... All original 1972 440, has a Performer intake and kinda crappy rebuilt ThermoQuad but otherwise stock. In the Polara it's got HP manifolds hooked up to a 2.5" H-pipe system from TTI; I'm thinking of transplanting the exhaust system to the Satellite and we most definitely want to step up to headers.

I read IQ52's great thread about the 1972 440 build, great stuff. My cousin wants to do a hot-tanking of the block but I feel like with the low mileage we may be able to leave the short block alone. Guess it depends on how it looks when I pull it apart and how much money he has, if the bearings look good we'll go from there. I will also do a compression test before we pull the engine. Anyway I'm thinking of doing a light port job on the heads myself; bowl and (maybe) guide blend and cleaning up the intake ports to match the manifold, also a good valve job maybe 5-angle? I also want to mill the heads to bring up the compression; we're at 5000+ ft. above sea level so it needs as much as it can get. Beyond that pretty typical stuff: RPM intake, better carb, Voodoo 268/276 cam+springs, headers etc.

My main questions so far:
1) What's a good amount to mill off the heads without screwing too much with other things?
2) What would be a good carb to run? I'm thinking a nice double-pumper like a Quick Fuel HR series but what about CFM? Want to be able to tune for decent economy as well...
3) Valve job... what would be the best option?