I have a few lifters making noise until well warmed up

take lifter out one at a time and pull it apart. Pull little wire clip (carefull they fly if not held by your thumb) with a screwdriver. Remove the seat, plunger, spring and check ball. The check ball and seat are under the little metal cap that can be removed with a pair of pliers. Soak in carb cleaner and clean each piece with a toothbrush, put ball and cap back on and reassemble. Put back in original lifter hole. You can do one in about 10 minutes if you can snake it out of the pushrod holes. you can submerge the lifter in 2 inches of oil in a can and push down with a pushrod. 2-3 pumps and the plunger will no longer compress. If it just keeps pumping, make sure oil passage on side is still open. youll find it.