E85 vs 91 for street

been watching this thread as I am well into a motor build that I plan to run E85 in.
I do the slant six stuff, already have a slant with MPFI with a MS3Pro running the fuel and ignition side, the car currently has a regular gas motor that has some work done to it, probably around 165 HP.
The E85 motor being built is planned to be a 300 HP motor, built using a '87 block, head and lightweight cast crank, raised compression, large cam, os valves, K1 rods and KB pistons.

Concerning setting the car up for E85,
* swapped in a Walbro F90000267 pump kit, that kit was an ez swap into the Tanks Inc canister
* added a AC Delco 13577379 flex fuel sensor, one wire to power, one wire to ground and one wire to the MS3Pro for the electrical portion
* confirmed with Areomotive that the fuel pressure regulator already installed is E85 compatible
* confirmed that the WIX 3399R filter that fits in the already installed Fram HPG1 is E85 compatible
* the car has a full return fuel system, mostly custom stainless tubing, there is about 6 feet of flex hose with AN fitting at the tank and engine ends,, I will change that out for PTFE flex hose with the PTFE fittings,, mentally I went back and forth on changing out the existing flex hose, figured that for a hundred or so dollars and a days work, just do it and then the hoses are done.
* I have an aluminum fuel rail, there is a shop near by that does anodizing, I'll get the rail anodized, then just like the flex hose issue, its done.

plan is to get the car going on E85 with the existing 165 HP motor, After I have confidence in what I am doing with the tune, swap in the 300 HP motor.