hi Tim, i see we are in the same part of the world, i am in Christchurch. Yes i got some of those alloy collars last year for my project haven`t fitted them yet i got A65 collets for my valves is that what you use? can`t remember where i got them from now but i`ve an idea that it was british spares Wellington, dirt cheap too as i recall,anyway good luck,cheers
Bob
