Hubs:
Both should fit, the 93 for sure, the 88 most likely. I think 87 is the break for the 8 bolt front axles. The red ones are the aisins. strongest hubs out there but way too expensive to buy new. I went with Warns instead of getting scrap aisins and rebuilding. Matt at indie has rebuild kits you an buy for the aisins.
Tire mount:
sounds like you are too far in, but have you ever thought, what I will do eventually, to creat a shelf in the back of the VX that the spare tire can slip under? I know my 285/75 would fit in nicely. The area could have some extra area around the sides, and infront behind the seats plenty of room for an OBA tank. you lose the rear seat though, but I think most of us are well past that point. Also, no external fabrication needed. its all contained inside.