"I transferred to the 747-100 next, there were design aspects I thought came off the VC10- I think some of the designers ended up at Boeing as British development wound down in the 60s."
You are correct. I went from the VC10 to the 747 as well and had the same idea. I knew one of the VC10 design team who became a curator at Brooklands. He confirmed that when some of the design team were let go from Vickers (BAC), they went to Seattle. The electrical system on the 747 is a direct lift from the VC10, except that on the 747, busbars sync was 1 to 2 and 3 to 4 whereas on the 10 it was 1 to 3 and 2 to 4.