Blueprint crate 408 long block- combos?

Don't worry about the 1pt. octane difference. IMO, though you hate it, use the 91/93 E-10 and dont worry about it. Do not use octane booster. It isnt worth the time or expense. However, keeping a few bottles handy for that "Bad Gas" day isn't a bad idea. Not just for every tank fill.

That ethanol aint good for old gas systems in the long haul --------