Hot Rods F-1 front shock mounts question

So I have F-1 shock mounts on the front of my I-beam transverse sprung duece framed '29 closed cab, I tigged threaded bungs on the outside of the boxed portion of my frame and this allows 7/16 dia. fine threaded fasteners. I have heard horror stories about not being able to keep these tight and of cracked frames, etc. Should I consider drilling through to the inside of the boxed frame and with more bungs use longer through-bolts instead? Maybe even heavy wall tubing tigged into the frame instead of the bungs? Advise please.

 

The threaded bungs if not large enough diameter could crack the frame around them. Sleeves that go through the whole frame and welded on both sides with bolts that pass through would be a better design..imo

 

Any place you can remove a threaded portion from your frame, and replace with a nut, is good. Might save you a headache down the road when the threads get buggered.

And the tube all the way through the frame sounds much stronger than the short one in the outside rail. So it's a win/win.

 

Confirms what I was thinking, I plan on drilling on through to the inside rail (boxed) and will either tig tubing in from the inside or just use two through-bolts from the inside and into the bungs, which were threaded 7/16 fine thds, but long enough to also add locknuts on the outside. Or both. Don't want this new duece frame torn up by a weakness here.
Thank you.