OK, here's the basic dimensions for the stock roof rack mounts:
Width = 39.0" between the mounting strips, 42.5" outside to outside
Length = 65.0" front edge to back edge, 48.0" back edge of front to front edge of back mount

I didn't try to remove my rack, so I'm not sure what the bolts/holes config looks like inside the mounts.

I took a few photos - not sure they'd be of much help. If you want 'em anyway, say so.

That rack you're fabbing looks awesome. Re: the 200lbs, my guess is that's the rating for the cross-bars for the stock rack. They're not too beefy. The main bars look pretty strong tho'

Tom
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