Lots of measuring and lots of double checking and I now have 2 solar panels on the roof of the Basestation.
I had to remove the original solar panel first to get to the junction box to connect the wires for the new panel using bluepoints, I also fitted a cable gland to the box as jayco just silicon the cable in
I did not want to run the cable from one panel to the other on top of the roof so I decided to fit a junction box on the roof for the new panel and run the wiring through the roof.
First hole drilled through roof
Juncting box fitted , sika flexed and wired up
Then to drill more holes in the roof for panel mounts
Fitted the panel to the roof with sikaflex 291 and peel riverts at front brackets and sikaflex and screws in to roof beam at rear brackets
2 panel up on roof all wired and ready to go.
Now just have to wait until we get the van out of the shed in a few weeks to check it all works.