I kinda see what you're saying but it seems like more effort than it's worth. I've also cut and rotated my knuckles which isn't that big of a deal but now you want to make it a driver's side drop for a taco. This seems like a good idea for the taco's running the 3.4L but for the 2.7L owners (me) I would rather stick a W56 with twin cases behind my engine with a driver's side drop. Then you can just use the 80 front as it is and use a T-100 rear for the width. As for putting an 80 front upsidedown, you wouldn't have a high-pinion anymore and you're gears would be running in reverse which I'm pretty sure would be a problem at mid to high speeds. Good thoughts though, I like how you're thinking outside the box.
