jon's kits are great, too bad they stop at 74.
hint,
hint again jon.
re the running bad a low speeds.
look for vac leaks, cracked hoses, loose fittings ect. plug the brake booster line and seeif it gets better, ect.
check your points settings and be sure they're at 28 deg of dwell.
does adjusting the idle mix screws on the carb change how the idle sounds?
if not those passages in the carb may be plugged.
mike