As Tim says join the MTWC also there is a Yahoo group which caters for the older 3 wheelers and has a plethora of information.
I am in the process of restoring a 1934 MX4 engined Sports. Starting it was daunting but once started you soon work out where to find the information you require or who to talk to. The MTWC has a good supply of parts and there are also a number of specialists in the older cars who can supply the parts the club does not have. The only thing I find is sometimes parts are not off the shelf and you have to wait until a batch is made.
If you are in the UK there will be a local group of the MTWC near you, where are you based ?
