Engine will crank but wont start

I recently did an engine over haul. After putting everything back together my engine will crank but not start. I have tried resetting the distributor, finding Top Dead Center again, checking spark, and fuel intake but still nothing. Also, I have a line on the back on the engine by the transmission that I have no idea what it plugs to. Things replaced: rear main seal, oil pump, clutch, throw out bearing, pressure plate, pilot bearing, control arm bearing, oil pan gasket, starter, slave cylinder, clutch master cylinder, water pump, harmonic balance, power steering pump, distributor, distributor cap, rotor, plugs, wires, get valve, ignition oil, head gasket, heads reworked and piston rings.