I tried out the other carb, and it works now. Engine still kicked backwards once before I got it started, though. Double checked the timing when I got it running, and it's at 30*. Didn't kick back as bad as before. After it did it once, I got the car started, warmed it up for about a minute or so at around 1600 RPM, then let it go down to 1000 and it idled. Now I need to figure out what the problem is with the other carb.