Found a random post on a Gen 1 forum asking for the chassis bolt thread and lengths, today had a spare hour so dropped them out and wrote them down, someone on here might find it useful so here's the results. GC/GD ( possibly newer ) and I guess whatever BC/BD and later liberties should be it too.
Hope that helps out. You might need to save it to your desktop or device to see the complete form, but I did rear and front subframes, manual crossmembers, front control arms and centre bearing.
Pete.