my car won't start

Hey, I need help here.
I own a 1987 ford country squire, in good shape and all.
When I bought it, the engine was bebuilt along with a new radiator, fuel tank and pump, exhaust system, alternator and so forth.
I had the transmission rebuilt not too long ago.

Now the car won't start! :mad:
The starter is fine, the positive cable is new and so is the solenoid.
What should I look for.

Help me. I have to cross-wire the car in order to start and that sucks.