Tried this last night and it seems to work great . Should hold up great but don't know yet.
1) Put scotch tape on one side of control horn to cover holes
2) Fill holes with baking soda using credit card to wipe off excess
3) One or two drops of thin CA. Wipe off excess.
4) Peel off tape
5) Drill out the now filled holes with a 1/16" drill
6) A light sanding if needed to smooth the horn
When I put the Dubro kwik link clevis back it it fits perfect! No slop!
I think it should hold up well since baking soda and thin CA are a pretty tough combo but I'll have to wait to find out. If it wears out I can refill and drill the holes in 5 min to be slop free again
Probably have to clean the horn first if it's full of oil.
George