I had my done many years ago by auto tech in chesterfield £70 a corner and it looked like it came from the factory it was that good , no cracks etc but I did take him a week to do off and on. Gently heating and rolling very slightly multipul times.
Just cut and clean then bond together , on my rally car they've sealed the rear quarter panels where it meets with arch extension and it's solid the only way you would damage it would be drilling it .

Cheers Paul