Can anyone suggest a method of making a hole?
My thoughts were
1. Jigsaw, but no real way of holding corrugated iron to wooden wall of garage so it will vibrate like hell.
2. Drilling a series of small holes round the edge of the 68mm hole and doing a join the dots with a pair of tinsnips.
3. Cutting the 68mm hole from the inside and removing the wood . Drilling the centre of the iron, snipping several cuts to the edge of the 68mm hole and trying to fold the iron back into the garage.
4. Cutting the hole with a pad saw with a metal blade.
I suspect once ive started with any method I'll have to carry on, so want to be sure what I'm doing before I start.