But...I think timing is off or 180 out. This is kind of my first go at a carb'd car and initial startup. Gas is getting to the carbs and oil pressure is there. But I'm getting a backfire..
Generally, a new topic would start a new thread, but since you hijacked your own thread, I will comment.
I think back firing -especially thru the carbs is a good sign the timing is off 180. If you have an early TR3 the oil filler cap is near the front but if it's a 3B, the oil filler cap is near the rear. In either case, you can remove the cap and see a pair of lifters. If you turn the engine over by hand (or bumping the car in gear) you will find a spot where the intake and exhaust are both closed fully (because you can reach inside the filler cap hole and wiggle both lifters back and forth since there is no tension exerted from the push rods at the spot where the piston is at TDC and expected to fire). This will also be in alignment with the hole in the crank pulley and pointer. So, on an early 3, the front (#1) piston at TDC (hole at pointer) and both #1 rockers loose (180 away from #4 in exact same crank position), with the dizzy cap removed, the rotor should be pointing at the same spot as the wire for #1 cylinder.
If not, you can swap wires 180, or pull the distributor and rotate 180. The timing can be way off and the engine still start, so start with the dizzy loose, and rotate it each direction about 10 or 20 degrees while someone is cranking the starter, and it will probably fire up if you are not out 180. Let us know how it goes, because the first start is always exciting for everyone.