That all looks good to me. The tapered spacer helps keep the carb level when under power; that's what I was looking for. If the fuel pressure is right (6-6.5 psi) then sounds like the carb needs to be tuned a tad richer with combos of main jet and PV.

It sure is helpfull to have an O2 meter when doing these things. Not including welding the parts for this are ~$100 from Summit, and you can make it permanent or temporary.

Good Luck, Kitz