I'm no expert but I've been around 2 different fixed calipers like this and they could both be flipped from one side to the other by switching plug and bleeder.
The reason I ask is I've found a few sellers on eBay selling brand new gm ats pass side calipers loaded with clips and pads for less than most pay for the bare caliper.
Ya looks to be just swapping the plug/bleeders but not 100% on that. I saw the ones on ebay and they are $100 more than I seen most paying.