Speedometer rebuilding. No info

so I searched all over the net for mopar gauge repair. Nothing. Everyone says replace the cable, or send it off. Well, I don't have 175 bucks to pay to have mine fixed. It fluctuates and never steady. Bouncing all around. I'm tired of looking at it now to the point of actually disconnecting it.

My question is, out of all the things FABO members have learned and knowledgeable about, nowhere can I find anything on rebuilding a speedo. Is this something like rocket nuclear fission science to repair a simple speedo??? Or is this an understanding that only those special people know how to do and they won't say anything unless you pay?
Has anyone fixed this issue themselves or did y'all just ship it off?