Don't worry Nick,
I started my Miglia in January this year with the intent of completing it to the same sort of schedule as my Sammio - ei about 5-6 months, and here I am in November and the body is not even on yet!
I got round to doing some wiring yesterday in the sunshine - albeit cold outside - and so I feel I made a little progress....
Spend the winter collecting all the remaining bits and do a tiny bit each weekend to keep your motivation! When the summer coms next year, you'll be ready - well that is my new plan anyway!
Good luck with digging out your Sammio!