Spent another few hours doing the fitting and finishing of this little job on the Lola.
The new flywheel weighed-in at 6.25Kg (rough kitchen scales) and certainly lighter than the stock flywheel but above the capacity of the scales so no real comparison.
Popped on the crank with a nice precise fit, all bolted up and the clutch back on.
Gearbox dropped back on as usual and I reconnected the hydraulics and all works, so everything back to normal.
While on a roll, replaced the split CV joint boot and even that went really well too!
Can't last.