I've got a '69 Malibu with the stock mechanical speedo and a late model TH-400 with the electronic send unit. Obviously the two aren't compatible. I've found three possible fixes:

- The Abbott Tach Cable-X electronic-to-mechanical converter.
- Switch the send unit in the tranny from electronic to mechanical.
- Convert to an electronic speedometer.

All options are comparable in expense. I'm leaning towards having the send unit in the tranny switched out as it seems to be simplest and most robust. If the tranny needed to be rebuilt I'd go with this right away.

I might go with an electronic speedo conversion. Can anyone suggest a brand/model that would fit into the dash cluster without any cutting

Thanks for any advice.

I had to change the Electric unit out of my 400 for a Mechanical.Wasnt tough at all...Hardest part was getting the Gear off of the rear spline,Once that was off...I just tapped the new one on,And put the other part in(Where the cable hooks up)With a new speedo gear(Green in my case) And was done.

If you dont have trouble getting the old gear off the spline,It is a very easy and quick job.

I went to a transmission shop in the area...He gave me all the parts I needed for a very low price.

Good luck.