You could also reverse the bolts on the gearbox mount and use countersunk head to gain a few more mm’s.
It's an idea, but I've never hit them yet, saying that the gearbox mount has proved to be a rather effective gravel scoop so those nuts must be colse.
The lowest point on Monty's underside is now the sump and I feel that's easily high enough to be safe, but it does all need testing on the worst of my local speed humps, there are some real shockers in my area so I feel confident if Monty can clear them he'll be able to clear anything our UK roads can throw at him.
I'll report back after a thorough test
