Rear cab mount after frame shortened

[karbias]

So I started with a 1968 C20 long bed. I cut the frame to make it a short bed, when I was looking on here to see where the rear cab mounts boltto the frame, I noticed that all the articles on here have the mount where it sits up above the top of the frame rail. So my problem is that before I cut the rear mounts off they sit down below the frame about an inch which you can see in the picture. My question is do I put the rear mount at the same height it was when I took it off or do I need to raise it up? Thanks for any information.