Keep in mind I'm not being 100% serious with this reply...
But then you'd own a GM. And it would be a vehicle that would be slower in every measurable aspect along with being less exciting to drive...along with being as common as a Camry or Accord. FR-S and BRZs are as common as Tesla's in my location... in that, on average, I see as many Tesla's as I do Twins daily...
Who cares about factory warranty when the car came with an underdeveloped powerplant to begin with that there seems no true fixes for? The hybrid Subaru motor/Toyota fuel system is the main issue with the 86 reliability... If you have the funds, going to a proven, moderate performance level LS V8 with minimal weight gain will be an improvement in reliability. Even uncompleted, the FRS engine bay looks nicer with an LS V8 than the corvette's does these days (GM has zero clue how to package engine bays without making them cluttered and UGLY, and they just keep getting UGLIER and messier looking):
Latest from GM school of Engine Bay (can you distinguish the friggen engine in this picture from the rest of the engine bay?):
Why would you ever want to lift the hood to look at that?! I'd be buying hood pins with locks just to make sure an innocent person didn't have to suffer that sight....
That's why I prefer Japanese cars to american one...the engine bay philosophy. Japan's most complicated performance car makes it look like GM hired toddlers to package engine bays:
But that leaves a thought to ponder, what would the GTR engine bay look like if it were done by GM...