Doing the whole brake system from nothing on my 71 chevelle.....im a bit confused when it comes to the metering valves and proportioning valves, blocks on frame? the only things i know about the brake plumbing is the hard line running front to back, axle lines, brake line on crossmember under the engine, and the flex hoses. Can someone fill me in on the valve blocks and small lines, also perhaps a place i can locate a 4 wheel disc prop valve and lines for it.

71 had a combination valve for disc/drum. It had both metering and proportioning inside.

If you are going with stock brakes, you can get the correct frame backet and lines and a brass combination valve, and it should all bolt up. For a stock system, the most likely candidate is the ACDelco valve 172-1354. For non stock, I would pick a different one, or use an adjustable.
search 172-1354 (http://www.oewarehouse.com/Merchant2/merchant.mv)

4 wheel discs, with that said, any recommendations on valves, metering blocks, necessary lines, etc?

You could use the drum splitter, and an adjustable valve spliced into the rear line (the drum splitter only has the warning switch). Then do the rear axle lines as required for your discs.

Or, you could get a disc/disc combination valve (there are 3 or 4 different ones which would bolt up to stock lines and bracket). Which one you use should depend on which brakes, and vehicle weight transfer mostly. It is kind of a guessing game on that, so the adjustable one might be the right answer for most efficienty braking.

If you dont need a warning light, you can run all the lines right out of the master, Tee the front, and put the adjustable somewhere in the rear where it is accessible.