I went through the same situation about a year ago with jims kit. I'm quite surprised the wrong kit is still being produced. I ended up making my own body blocks out of white oak.
Here's a link to my measurements vs jims blocks. body blocks


I'll call him direct over the weekend and let him know there's still a problem


1951 3100 Chevrolet
1951 Chevrolet Suburban Carryall
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