Exhaust - hole in bodywork

I had to cut a hole through the bodywork for the exhaust. The question was how to get it exactly in the right place. I took a hint from the FM site and made a cardboard template that fitted to the chassis:


With the bodywork back on the chassis, I marked a circle through the template, found the centre and drilled a pilot hole:


Then applied lots of masking tape to the outside to protect the surface as I drilled:


Then finally I cut the hole using a hole saw:


When the body was replaced on the chassis and the exhaust fitted it was perfectly centre in the hole: