vanguard

I have a '95 4X4 hardbody and recently I ripped the sidewall on my left rear tire. The tire was damaged beyond repair. I was unable to find a used one so I ended up having to replace it with new (identical brand/size). The tires I have on the truck at the moment are BFGoodrich All Terrains (235/75R15). The old ones have about 40-50% wear, so the diameter on the new tire is about 1/2 inch larger than the old ones. My questions are:
1) Will the difference in diameter strain the drivetrain while in 4X4?
2) My differential is now 1/4 inch higher on one side, will this cause damage?
3) Will my alignment be affected?
4) What would be the best place to have the new tire (front or rear)?

I was hesitant to replace only one tire, but did so since I plan to replace all four with a different size once they wear down a little more. The guy at the tire shop said having a new tire amongst old ones won't make a difference. Your opinions and comments would be greatly appreciated.