Happy ending to my modded MkV saga. Atomic took the amp back today for a full refund, with zero hassles, as promised. They have an amp tech there who used to work for Mesa, and he's going to go over the amp and get it back to stock. They said if I wanted to buy it after that, they'd ship it to me. (I didn't inquire about shipping charges. Still have cold feet, and will probably take a break from this particular gear diversion for a while.) But anyway, great bunch of guys down there, as per their reputation.
Special shout-out to my wife for actually running this errand on my behalf - driving 300 miles to drop the amp at Atomic, then visit her sister for one night, and then drive all the way back the very next morning.

(All this to beat the stupid snow storm that cancelled what was supposed to be a week-long visit.)
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