I fixed an 18" long section of frame on my 99. Took me about 20 hours to design a 1 piece 3 sided section that would go over the rear axle hump and all the way up to the rear crossmember. Then I slid the 3 sided box over the top of the frame to start making the box and cut the 4th side for the bottom. Welded it all together and into the frame and it's good as new.
OP there will never be a frame recall for these things you either scrap your truck, get someone to patch the frame, or get a rust free frame and swap everything. Take your pick none of them are fun.