First smother your engine with some sort of de-greasing stuff. I know it looks like shaving foam, but it's actually Mr Muscle oven cleaner !
To undo the flywheel bolt just stick a 1/2 inch spanner on one of the nuts and then bolt the other end to the bell housing.
If your gearbox sounds noisy, it could be that you have 'accidentally' fitted stright cut drop gears. Reverse whine in all gears :-)
Within a matter of hours your pride and joy can be reduced to a few large piles of bits!
Then you can start to think about upgrading things as you rebuild it
Nasty standard diff compared to nice spangly 4 pinion diff.