You're fine with fuel pressure. the fluctuation is probably just your gauge being really finicky. I have an ISSPRO EV2 and it fluctuates like that. Except mine drops to 25psi when I go WOT!

 

25! Ain't that injector killer?

Ok I'll go back to my original post and back to the drawing board...

 

So they say... I'm also reading pressure behind the heads past the last injectors too.

I know I'm getting fuel though, since I still have black smoke that isn't clearing up. It's a work in progress and I'm learning as I go. Once I get some hard facts about what's happening and what I find, I will be sure to share!