The first parts I got ahold of was a new k-member and lower control arms, they were super rusty but cleaned up well with sandblasting. The next step was weld over all the seams and box some areas off. I did the exact same thing with the old k-member on page 2 so there is no need to go into much detail.
When I went to test install this today I realized that the passenger side motor mount is different but more importantly the idler arm mount is not the same. I think the new one is from 67 which has a different idler arm, so this will need some modification..