Hi Jean
Hopefully you will get Hector sorted and back up and running ready for when they let us out.
When we bought Helga, she had a rust hole which was highlighted in the mot and fortunately fixed by her previous owner.
Once we had her, we took her here : https://www.rust.co.uk
They cleaned, rust proofed and then sealed the chassis. Not cheap, but it looks fantastic, all black and sealed. They guarantee the work as long as you have a yearly check.
I am not affiliated with them at all, but they did a very good job.
All the best
chris