Camshaft question
A looooooooooot of expense to change cams when no tuning has been done to dial in this cam.
Rich idle, surging, are all part of engine tuning. Getting these things correct will more than likely result in smiles all around.
Idle timing is the first thing to get correct [ NOT the carb ].
So check the timing, in gear, & report back [ hint: it may not be this much now, but it might want 40*..or more ].