I agree, Richard. I can only imagine how much stress that places on the top though. I'm thinking it must be specially braced or reinforced somehow. I noticed he didn't make use of the Bigsby at all during this particular song.
Here is a link to a listing in the EBAY section here on the Forum from last year where someone had a F50R with the same Tremolo setup on it for sale. The photos are gone in the EBay listing but there are 2-3 pages of discussion on the guitar itself.