So, ages ago I bought a universal flywheel locking tool, but it doesn’t fit my lightened flywheel at all well. So, I’ve made my own. It took less than an hour.

All I did was trace the outline of the flywheel onto a bracket, and then cut and weld it to a piece of 20mm square tube.  The tube was then drilled and bolted to the block. It’s a nice snug fit and should be able to take the load when the crankshaft bolt is tightened 100Nm + 90 Degrees.