Originally Posted by Retro Grouch
Not one that I've ever tried. The test would be if the left crankarm hits the chainstay. Depending on the crank it might work well enough to be rideable, but I think that it's kind'a nice to have the crank centered on the frame.
It would depend on the length of the spindle I suppose... and the amount of adjustability available in the cups.
Ranger, if this is an old adjustable bottom bracket, the cups are certainly interchangeable between 68 mm and 78 mm shells--provided that the threads match.