I reckon a pair of doors in HFF would have been a lot lot easier, and you would have been surprised at how easy they are to change.
The whole job would have taken less than a couple of hours start to finish, and probably cost less than the rattle cans and tins of bodge.
Where in Northumberland are you, I know Colin "2Diesels" has a HFF tourer, and knows where there is a saloon breaking
Just a thought, especially as you were evaporating the solvents in the paint with a hairdryer, the pearl effect of BRG will certainly have been lost
Brian