Hey Higgy I been following your build and it's quite a work of art you've put together there! I'm sure the pictures do the bike no justice, it probably looks 100x better in person!
With that kind of power plant, I would run the +4 swingarm, I don't think a +2 is going to keep your nose down. I run a +4 on my 420BB and my front end barely stays down and I'm 290lbs..