After stripping everything off the original door, I had a bit of work to do to scrape off the remaining glue and remnants of laminate, and then sanded back the rusty areas to remove all the loose bits of rust.

After that, I gave the whole frame a thorough coat with Penetrol to help seal the rust and prevent it getting any worse. I even used the existing holes in the frame to squirt an entire can of Penetrol into the inside cavities.

Now that I had the door frame cleaned up and protected, I moved onto the frame inside the bus. I wanted to remove the stainless steel trim so that i could see the steel frame behind it and work out where I could bolt on the hinges. Unfortunately, removing the trim revealed yet more rust! Not surprising, given my previous issues, and the fact that the door was leaking badly. But disappointing nonetheless.
Thankfully, most of the main vertical pillar was in good condition, and it was only at the bottom that the rust was an issue. But, it was a BIG issue! The very bottom of the pillar was completely rusted through on two sides. It will require cutting out and a new piece to be welded in there.

Unfortunately, my welding guru friend who did the last welding job for me, lives in NSW and because of the Covid restrictions, cannot cross the border to come and help me this time so I will have to sort out some way to get it fixed..