First time engine build won't fire

I have a 360 i rebuilt it is my first time and I took my time doing it to avoid mistakes but I am beginning to feel like I've missed something. I have the motor in the car now a 74 duster, and for the life of me it will not fire. I found that i had the distributer drive gear clocked in wrong i have since fixed that and I've checked my wires again and again and it still will not fire. I am getting spark and fuel in fact it is spitting gas back out the carb. Any suggestions ?
have you checked to make sure you have the timing on the correct stroke?