8.8 swap

#3 sounds like the logical choice since their readily available and they'd put the shock mount right were it'd need to be but why would you need to "oval the holes" to make them work? Aren't the 8.8 axle tubes the same diameter as 8.25/8.75" rears?

They are 3 1/8" tubes. If you just clearance the holes a 1/16th on each side, you should be all set.