Wont Start, Help

Okay, this shouldn't be a mystery. I'll give you a list of things to double check, even if you have already checked them 5 times... no kidding, do yourself a favor and check them again. It's always something that I was SURE of that bites me in the a$$.
Let's start with the easy stuff...
Does fuel shoot into the carb bores when you pump the throttle? (It should)
If you have fuel, I'd next check the timing.
Make SURE the rotor is pointing straight at the #1 plug wire when you are coming up on the compression stroke of #1 cylinder. Number 1 is the front drivers side cylinder. Sometimes you have to go as far as pulling the valve cover off to make sure both valves are closed on number 1 to verify it's on the compression stroke. And remember, when you are placing the plug wires, the big block rotor turns the opposite way (counterclockwise) from a small block. The firing order is 1-8-4-3-6-5-7-2. I've seen several good mechanics get confused due to the opposite rotation of the big block distributor. If memory serves, the #1 plug wire will go on the low (passenger side) of the cap, and it will roughly line up with the front corner of the block, sort of pointing at the fuel pump or alternator.
Number 8 will be the next one in a counterclockwise direction.

If you find that you can't get the number one plug terminal even close to where it should be when the the #1 cylinder is at TDC on the compression stroke, either you have the distributor in 180 degrees out, or the cam timing is wrong.

If you have fuel, and get the timing close, and there's compression it should at least start and run.
Good luck with it.