72 360 first start question

So i just finished a 72 360 block and fired it yesterday. I primed it really good put the oil drive gear back in and set the distributor pointing at #1 cylinder while the motor was at TDC. It fired up fine, but i had to keep the throttle on pretty hard to keep it going. I had a couple back fires while i was trying to move the distributor for timingbut nothing crazy. after i got it to run for a while i called it a day. This morning the thing wants to backfire like crazy out of the carb. I even got a little flame in the carb for about 5 secs. until i got it out. I've built tons of cars and blah blah blah but never had a campfire in a carb. My questions are 1 do you think the carb is cooked and could that make the car explode!? and 2 if it's backfiring out of the carb that means it's too advanced right?? not retarded. I tried retarding it quite a bit and it still didn't want to run. I usually have a buddy around when i'm doing this kind of stuff but i'm solo on this one and don't really wanna light my face on fire. any suggestions?