2001 Silverado OS upgrade for e85

I'm looking to put a turbo on my 2001 Silverado 1500HD with 6L and 4L80E. I have e85 available around me, so I've been thinking about tuning the truck for it. We take the truck on many long road trips, so I've been looking at adding the flex fuel capability (sensor and OS change) or just pulling out the laptop and flashing in a 93 octane tune if I can't find e85. My truck currently has OS 12208322 in it and OS 12216125 is the only P01 OS with flex fuel enabled. My question is, other people with early GMT800 Silverado's, will going to the flex fuel OS break any functionality in the truck (ABS, cluster, trans temp gauge, ...)? I looked and ABS modules are different between vehicles that came with the flex fuel OS and mine, so if something major is not going to work, I won't waste my time with the flex fuel OS and just flash the truck if I can't find e85. I can apparently do a segment swap between the flex fuel calibration (2002 Tahoe) and a 2002 avalanche with 8.1L to retain the 4L80E. Also, since my stock 2001 OS can run dual electric fans, I'm assuming the flex fuel can as well (same drop downs are there. I'm concerned reading online that the ethanol content in e85 varies a lot depending on season and the sensor plus flex fuel OS would help me with that. If anyone just flashes back and forth between changing fuels, I would be interested to hear your experience on fuel too. Trying to figure out a path forward. Thanks for any help.