I am also based in the Uk, in September I started a rebuild on a 55 and sent an order to Truck shop, after what seemed ages, I tried e mailing them, but never got an answer, I then had to call them ( not cheap - especially when they put me on hold for ever)it turns out that the windows I had ordered were not available, neither were some of the other bits, I felt I had such a poor response to my orders that I cancelled the whole order and went else where, since then I have spent about $5k on rebuild parts with various other Uk & US based vendors, and I am glad that not a penny went to Truck shop, their loss on this occasion and I would never recomend them to anyone else in the Uk.
Chevy Parts - Uk based are superb and Classic American are very good also.
Now don't even get me started on CPP !