vauxhallviva.com

Hope this help someone...after struggling to remove a sticky pinion extension I sussed it..... Clamp one of these 'tri-clamps' around the pinion and then use a normal 3-leg hub puller. The clamp gives the puller legs something to grip on and it pops it off no problem.

Te clamp diameter size you need is 2in.Tricky to find on Ebay until you use the correct term 'tri-clamp'
Cliff