spa has L1 and L2 with a common and a ground terminal

I have run 4 wires - 2 blacks 1 white 1 green

the GFI (BR50A ) has a ground terminal and 2 breakers with one breaker has also a white wire atached to it that goes to a second block.

OK so I think " black goes to L1 and second black goes to L2 " white goes to common and green goes to ground.ON spa
If this is correct then in the GFI does the black L1 go to breaker1 and the other black L2 goes to breaker2 the white pluges in to the breaker with the white wire attached and the green goes to the terminal in the GFI then -------

I have a big 3 phase switch on the wall there are 3 wires hooked up to switch " 1 white 2 blacks" and the green is screwed into the box. Is this correct.?????

Sounds correct.

http://spasupport.com/electrical/main/installguide.html