Otto, thank you very much for the quote - really appreciated.
Megaglide , I understand your confusion. I have found a very good mechanical shop here in Belgium but they are not used working on HD parts and want the precise size for the bore. Through 'a friend of friend' I have access to the tools of a HD shop - and yes I could ask them too - but over here all shops just say buy the big bore cylinders, but as the prices of all HD parts are double the price or I have to pay quitte some shipping costs I would like to avoid that and bore them out.
Jef