Crossbars too far apart for roof box

Hello

My truck came with this fiberglass camper shell. The previous owner mounted a Yakima 1A raingutter system to it. I have a Yakima Skybox 16 that I’ve had for years. I’d like to figure out how to use it with this camper shell however the bars are at a fixed distance apart, which is 10” wider than the maximum adjustability of the box.

I’ve played with the idea of a third bar but these towers and especially the Sideloader mounts are unobtainium these days. I’ve also thought of adding tracks on the roof but it seems redundant, plus they’re out of stock from Yakima.

I’d like to not dump a ton of money into this solution as I’d eventually like to get a taller shell. I’ve played with the idea of making a lattice out of aluminum extrusion and mounting it between the bars.

What options/solutions am I overlooking?


(Photos of my “new” truck and former 4Runner for content)

 

I put 3 pairs of gutter plates on mine. I got Rhino rack gutter plates from their website.
You can find some used Yakima 1A towers somewhere. There must be a ton of these leaning up in the corners of garages. Check the paddling groups on fb... like 'whitewater gear for sale'.

 

Drill new holes and move one or both racks.

 

4 1A towers for $70 on the fb page "Kayak Classifieds"
Comes with cross bars etc

 

I found this ad on craigslist for the shell. The owner has the same roofbox and bar spacing as I do. I messaged them and they said they modified the tracks of the box to move the mounts further apart. Free solutions!