I'm wanting to change out the differential gear to something higher so I can get better top end speed (54 mph at 2200ish is about all I get now). I just talked with a local shop and without knowing exactly what is in there, he quoted me $2500-3500 + labor for the job. That seems a little steep to me, but I really have no idea. I have no issue putting a used gear in there, but not sure where to look to find one. I've got a 1990 Crown, DD with a 10-speed Roadranger. Does anyone have any recommendations or suggestions?