Thanks for your replies Ken. Yes it is quite a list, but I can see myself making or modifying most of the items. Re the switch knob, I've just accessed the Ebay link and the item is interesting, but I have a Lucas item which I may modify in the way that you suggest. Nice idea about 3D printing! I'll need a key from you at some point, to go with it. Could you email me the carb spec please? The one that has been fitted is the wrong 'hand', so that the tickler is on the wrong side and is inaccessible through the bonnet hole. I've been thinking also of using a later S22, or even an S25, because it won't be seen when in use. Do you have any experience of using these later Villiers carbs? Cheers.