tappet adjusters excess play

Hello everybody

I am a newcomer and I thank you all for guesting me on this forum.

I have a '58 Belvedere (almost daily driven since 35 years now) 4DRHT with the power pak option.

I have a problem with the tappet adjusters... Some of the adjuster screws have lost they snug fit into the rocker arm and don't hold the setting.

I will try to attach a couple of pics.

I thought that a moderate blow on the side of the rocker arm (in a vice, of course) could restore the snug fit..... or it's just a crazy idea?

Any hint?

Previously I put some thread locker on the adjuster thread but this stopped the oil supply to the cup of the pushrod, resulting ina worn out pushrod cup.....

thanks for any help !!!