1983 motor mounts mod

[Branman1971]

So I'm going from 61 front crossmember to 83 with power steering and disc brakes and now I'm looking at the 83 motor mount perches. I am going to install a 396 so I would rather use the 83 perches than the perches that I got with the truck and the 350. I can't find any posts about modifying the perches because the frame is taller on 83 then a 61. I can probably figure this out but it would sure be nice to see an example. Here's a picture of my original perch on the right and the new perch on the left. Quite a difference. Thanks y'all.