Job done. I found that a 19mm ring spanner fits perfectly over the three pins on the flywheel and this held it tight while I loosened the nut. The sprung loaded pin was stuck pretty tight in the crank but a couple on taps on a small punch did the trick. All cleaned up and free as a bird now. Now its time to get a cuppa, sit down at the kitchen table (when the wifes at work of course) and get it all back together again.