Aye Dave,
If you can bake or get somebody to bake the VHT for you rather than relying on exhaust to do the job, this will improve the longevity of the coating. I've a supportive wife for these eventualities,

so the fan oven is pressed into service if the exhaust bits will fit!

S*d the 18 pound turkey!!!! I am toying with the idea of a ceramic coating job, BUT, life in general is preventing m/cycle tinkering!
However, last night another 'early retirement' from the Agency I work for, meant that Sally had a good canter in the dark. The Tahli wasn't bad either, with a garlic nan, to mop up with!

My regards, Bill.