They re extremely easy to make and pretty cheap.
How to make your own towers for roof rack.
The tolerances for the nuts are tight and if you use a bit that is slightly over sized the nut won t crimp properly and you ll be screwed.
I ve always wanted a roof rack for my land cruiser but the commercially available options didn t fit my needs so i made a custom one come see how.
Drill cordless or otherwise with a drill bit that is exactly the recommended size for the rivet nut you are using.
If you can use a tape measure grinder chop saw and can half ass weld you can fab these gutter mounts.