There are several ways to lock the engine so you can use a bolt to remove the Flywheel.
I have a small gear from a CX gearbox I use at the front of the engine on the Clutch gear,
http://i42.photobucket.com/albums/e315/ ... nklock.jpg
You can use a coin,
http://i42.photobucket.com/albums/e315/ ... neLock.jpg
Some people have also just used a rag between the Clutch drive gears.
Always check for debris from anything you use.
Whilst you have the front cover off you can remove the Oil pump chain and oil pump and check the Oil pump strainer and clean it and underneath it(The sump).
When you replace the oil pump use thread lock on the small 10mm M6 bolt that holds the oil pump driven gear.
Please refer to the manual for correct fitting of all dowels and O-rings and the oil regulator(The small alloy spigot and it's O-ring)