All Plugs Fouling on Right Bank

Did you chamfer the holes first?
If not, I highly recommend that you start over.
I did. When I was done, I tapped the solder on both sides and it felt solid. Your instructions were great. I also found online another guy with the same problem with an RC airplane carb who did the same thing. That, plus a beer, emboldened me to try it. I'm touching up the intake manifold now and putting the carb back on, then calling it a night. I'll fire it up tomorrow.