2000 units are wide bodies. 75's are narrow bodies. The outriggers would not be the same. The 2000 frames are deeper and stronger, if you could get it to fit.
If you had the original frame as a pattern, you could have a new frame built to those measurements. I would use 6" structural channel rails with 3" structural channel crossmembers and outriggers. Angle iron could be welded onto the side of the 3" channel if you wanted something easier to attach to.
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