6000 is the red headed stepchild sos only machine.. limited parts support.
8000? the usual stuff. some tranny parts are priced outta thuis world.
I'd for sure think a 5000 or 7000 would be a gread machien to climb into. stepping a lil newer.. 5600, 6600 7600.. etc. on into the 10 and 10/II series.