I am getting an 80's Nishiki Riviera GT frame that I'm planning on using for loaded touring. From reading in the forums the BB housing is most likely 68mm, and the rear spacing is 124mm (planning to cold set to 130mm). I'm planning on using Shimano 105 hubs with an 8sp cassette and a Sugino XD triple crank (26/36/48).

The frame comes with a BB installed and I'm wondering if I'll need to replace it. Is it likely or unlikely that an 80's BB will work with the hub/crank setup I mentioned above?

Also, if I decide to replace the BB I need to know what spindle length to use. How do I determine this?