It ain't no hole for a switch or a mod. Unfortunately, that amp is as hot as a pistol. Too bad! I would not want it in my possession! And the seller really doesn't have any choice. If it's reported to ebay, he will no longer have an ebay store/account, nor a paypall account. I have friends who barely eke out a living with their ebay stores, and I'd hate to see that happen to anyone. But he's got to take what may be a devastating monetary hit, and get out from under this. Ebay is very strict about selling stolen goods, goods with missing or altered serial numbers. I'd bet the guy had no clue about it. Bought an amp, it sounded good, and he sold it. Unfortunate set of circumstances for all involved!
At least,,, that's the way it appears right now.