Note crimp in leg of  TC3.  These legs are very tight to the board.  This cap does not adjust smoothly.  When the legs are forced into the holes they deform, and affect the body of the capacitor.  When I was inserting TC5 as careful as I was, the one leg buckled.  When I tried to pull it out to straighten the leg, the leg broke off the capacitor.  I replaced the cap with a fresh one.

I am considering order a half dozen of these variable caps from Mouser as spares and also some other ones that have conventional legs, and even some SMT ones with a similar spacing.  These legs have a barb on them that tends to jam in the hole.