I found a 145 speedo on ebay for $5 so I bought it. The catch? It is missing the needle and needle shaft. However, the guy thru in a beautiful, pristine 85 speedo for free.

I started disassembling the 145 since it doesn't work anyway, to see how these things work. On the back of the 'guts' assembly, I noticed the part numbers are the same for the 145 and 85.

I know it has to be more difficult than a face plate change. I did a search on this but all of the posts were dead ends. What do Ihave to change? I am gonna try to disassemble this one a little further to see if I can get the needle shaft and torsion spring off the 85 and into the 145.

Any tips would be great.

As far as the odometer, I am gonna pop the 145 out and replace it with my 115 currently in my car.

 

The torsion spring at least is probably different, I don't know what else would be.