Frame holes as far as I know are not needed. Mostly they are there for machines to hold the pieces together when they are welded together in the frame factory. I been welding them shut since the late 1990s. As in the rust belt. They let all the salt water and dirt into the frames. { That is entirely up to you if you leave them open or close them off its just what I do }

I use black steel gas pipe with 43 inches long with 1.5 inner diameter which is really close to in Outer diameter. The sidewalls of this pipe is nice and think close to (1/4in ) {I think its $25 or $30 bucks} I paint the pipe with gloss black rust-oleum. Then I coat the inside of that new pipe with fluid film. I either plate the pipe hole shut or use a rubber body plug to seal that tube up in the wheel wells in each side.

Those give you something to weld the upper control arms brackets back to and your coil shock plates.

If that original pipe is rusting through, really check out those brackets and your coil plates. I have had one of those coil shock plates come loose by rotting off the frame once.. Those are not easy to reattach at all. As their location makes it extremely difficult.

Don't forget to send us photos. I enjoy seeing folks frame repairs.

I see those kits go over the original frame. Do they have any instructions with them?