I am mounting 3 drivers in a project housing. Can I solder batt - wires to outer ring and batt + to center?
Yes, in short. I suppose you got around to that headlamp project?
Yes. Order from mtn electronics just came in. Would clamping to a small aluminum bus bar to help dissipate heat be better than soldering?
You mean the driver? They will get warm, but not terribly so at this kind of power level. I don’t think I follow exactly what you’re asking