This is one of those jobs I have been putting off for a long time, I just couldn't work out in my head how to do it properly and neatly, and how to have the door not take up any space.
Finally, I settled on a sliding hatch, the door will hide behind the seating when open and only sticks into the cabin by 40mm.
Once the cab is cut out, I will make a flange that will fit in the hole and a seal on the end of the tunnel will mate with it. An additional cowling will then fit over everything as an additional weather tight measure.
Many thanks to my buddy Dirk, who is far better at welding thin sheets than I could ever be.
