Thanks Jjankins & Crew21_Adv for your replies.  Actually Gilwell Park is just another camping ground in England and from their reply don't have anything to do with WB other than being a place where it can be held - but that was a good suggestion for a starting place - thanks. 
  Crew21...I lived in England for 8 years, left in 2006, and was active with a Scouting troop in South Ruislip, you validated what I was afraid was the answer, and what was suggested to me with a wink-wink by my English Scouting friends i.e. that it is a select group via invitation and not overly keen on American participation. 
  I suppose that, other than bragging rights & my personal vanity, there is no substinative reason to attend WB in the UK. 
  I'm going to snoop around a bit and will post any findings. 
  Thanks to both of you for replying. 
Cheers, SkyPilot06