[Second Series]

I considered modifying the transmission output to run a mechanical cable. The original discussion about this that I found on another forum was actually started by someone who does modify transmission tail housings. That thread was taken over by a discussion on making a motor drive for a speedometer. There was no final answer to the speedometer drive on that discussion, it went on for a couple years and just fizzled out. I have something that kind of works, and I’ll keep improving it until it is a finished product. It would be easier to just buy an off the shelf solution, $300 is not bad for a working original speedometer considering all the time I have put in so far.
There are some detailed write-ups online about converting from mechanical to electric, so easy enough to do it in reverse. I’m working with the drivetrain from an ’88 K2500, so NP241 transfer case. I can get a rear housing from an ’88 to ’89 for mechanical speedo for $200? Drive gear $80, and driven gear $12. An in-line speed sensor can be placed on the speedometer cable to generate the 2000 pulse per mile for $100. I still need a DRAC since my DRAC is integrated with the gauge cluster in the ’88 GMC, so another $40? If I did this, I might be inclined to eliminate the slip yoke on the NP241, so $500 for that kit.
Klowacky, I read about thar mod on-line in a very detailed description. That looks like a clean solution.
TrybalRage, Thanks for the encouragement. I’m interested in that project, I’ll try to find it. I looked into RaspberryPi vs. Arduino, and found the RasperryPi is an entire computer, operating system and all. Arduino is just a microproccessor. They are both the same size. As this project evolves, I will do away with the arduino, and just use the IC with the code on a custom made pcb.