If you are not using methanol in one tank, I don't see a problem with using some switched tank feed, should you be able to find one that could handle AN -10. You're going to have to run whatever through the lines for a bit when switching anyway. Race gas to pump isn't an issue IMHO like going from alcohol to gas. You just have to lose a few partial $ worth of high buck fuel in the -10 lines.
If it was me, I'd use come out of the tanks through a -10 AN Russell shutoff valve on each feed into a Earls -10 o-ring Y fitting, then run out to the filter and A1000 pump. With the right fittings, the filter, Y and shutoffs could be plumbed together as a unit. -10 female to straight thread o-ring adapters required.