New to E85. Getting a baseline...

[CVD]

This is regarding my 4G61 turbo Colt. Stock turbo, enough fuel mods for E85. On to the problem:

I just went from a 1G MAS and 450's on gasoline to a HKS VPC/GCC with 550cc injectors on E85. I feel as if I'm running ridiculously rich though, and have been leaning it out a little at a time. I'm just afraid I'll go too lean.

To start I went +30% across the board. Now I'm maybe at like +25%? Thing is though, I used to hit 70% duty cycle with the 450's on gasoline, in a 1st or 2nd gear pull on a cold night. Now I'm hitting 90-100 duty cycle on the 550's in any gear. So that's like a 40% jump in duty cycle PLUS 20% larger injectors. Am I doing my math right here? The VPC has a 550 chip so it should "zero" with the injectors.
I'm also getting a shit-ton of knock until the car reaches operating temp. Is this rich knock? Is it common with E85?

Is it safe to just lean it out until I see knock then add like +2% across the board? I'm only running 20psi (fading to 16psi at redline) so I'm afraid it's going to be really lean before I see any knock.

I'm getting no knock now, and it pulls strong at WOT. Just stumbles once in a while during cruise and I'm seeing crazy duty cycles at WOT and sometimes while cruising (like 40% under mild acceleration). Also the top end feels a little doggy. Boost from the 11b falls off pretty quick, but duty cycles seem to keep climbing to redline.

As for a real dyno tune, I'm going to tweak it a bit at MAP's dyno day, then slap the 16G on there and get a real tune a week or two later. I just want to drive and enjoy it until then.