Hi Stewart and welcome to the forum,
As far as the missing parts are concerned, you can create new ones from the plans. There are various different methods ranging from 'pricking through' to 'ironing-on' to the wood using carbon paper. Alternatively, photocopy the missing parts, cut them out and paste them directly to wood.
I expect some of the others may be able to help with assembly /templates if they have built the model – I know it was very popular in its day. There are some videos on Youtube which may interest you. Also, have a trawl through some of the build threads on the forum – there may be some thing there…
Good luck,
Dave