[64shortbox]

ebaby35,
When you say support piece - are you talking about the main saddle piece That bolts up with 3 or 4 bolts per side? If so, yes it bolts up in the same location as your 64 main saddle. You will need to hog out one mounting hole per side. If I remember correctly it takes 7/16 - 20 bolts but don't hold me to that, it's been several years since I did my Disc swap. I bolted my saddle in place with the holes that lined up, For me the easiest way to hog out the bolt holes in the frame was to use a drill bit for the size thread hole as if you were going to tap it, I ran the drill through the nut side of the saddle through the frame then ran a tap from the nut side through the frame if that makes sense.