Shifting is somewhat stiff in and out of gear which is ok, but the throttle movement itself is pretty stiff. Is there a friction adjustment anywhere to fix this?

Cable looks to be knew, binding feels like it's coming from the shift housing.

Thanks-

Going to a 496 if it makes a diff.

Start by disconnecting the shift and throttle cables from the engine. Check control box for stiffnes. If still stiff, replace the control box. Had same problem with Merc Commander controls . It had twin engine set up and both boxes went bad.