So I'm safe to say that the low in a 2 speed with 4:88s would be 6:24...
Yes, or something real close to that number (assuming 4.88's were ever available).
Am I safe to assume that I would be able to pull the 3rd member out and just swap it with the new one?
Yes, as long as the 3rd member cases are the same...take lots of measurements and pictures of your bolt pattern (the bolts that hold the 3rd member to the axle housing) and start looking around to see what fits.
Mike B
