Rain water gutering system for a polytunnel

My company sells and installs greenhouses and polytunnels. You can find more information at http://www.polyecogreenhouses.com

The most popular product is The Classic, which is an arch-shaped polytunnel. I would like to construct a rainwater collection system that would suit this type of polytunnel. I can buy guttering at Wickes etc, but the problem I have is how to connect the guttering pipes. The polytunnel cover is a twin-wall polycarbonate sheet. The sheets are 2.1m wide and they overlap each other. If I try to connect the guttering pipes, at the place where the sheets overlap I get a 4mm or 6mm gap.

The item I need is some kind of offset connector. Something like this https://www.wickes.co.uk/FloPlast-76mm-MiniFlo-Gutter-Union-Bracket---Black/p/176260

The pipes I would be using are these:
https://www.wickes.co.uk/FloPlast-76mm-Miniflo-Gutter-2m---Black/p/176257

I would like the drawings and a prototype to be printed, and if it is suitable and works, I would then require 100x -200x units printed.

Please let me know if that is something you could help me with.

Kind regards,
Elvis Bruss