I iterated on the first angles and simply made them a little longer and doubling the amount of fuse holders. This makes for a very robust solution that can easily hold two large lamp modules.

I'm quite satisfied with the current solution. I jig would be nice for soldering though, it's not very easy to solder them at perfect 90° without something to hold everything in place. The one you see below is more of an 80° angle.

And of course easy adjustment in height: