Someone school me on converter/pump relationship please!

"Bogging the engine down" is not a function of the covnertor. It's the function of the tuneup. Generally the timing is not as far advanced as it needs to be, and/or the carb is lean at idle (whicch may require air bleed changes). For what you have - you shouldnt have a 10". That should be an 8" IMO. It will feel loose on the street but who really cares. If you wanted a cruiser you need to rethink the combo. that's a really nice strip/streeet combo and needs to be assembled as such. At least all in my opinion.
personally - I'd call Lenny at Ultimate Convertor Concepts.