what size injectors are needed for this much HP?

Depends on what type of fuel you are planning on running. If you want to make 500 on conventional fuels, then 1000cc will be ok. I think that mine were at like 80% duty cycle. If you plan on running E 85, then you need 1600cc injectors.

Yeah, i have known Tony since he started at Jotech. His shop is right down the street from the Land Cruiser place I used to frequent. They had a ton of FJ'S.