9-inch Fab - need perch distance

[68bowtie]

I'm welding new perches onto a 9-inch to bolt into my 68 sb c10 with trailing arms. I've got everything ready to weld in place, but I want to double check the stock perch distance from center to center. Can't seem to find a reference. Thought maybe someone could crawl under theirs and measure what they have on a stock rearend.

I'd appreciate the help.