I got a electronic speedo off ebay and the needle is a bit different and doesn't have that silver peice in the middle. I'm wondering how easy or hard or if it's even possible to switch the 2. The one I got now is the original mechanical one. The new one is from a 911 of some sort.

here is the new one

I did this for my '73. I used a speedo from my '74 donor and the needles are different. You need to remove bezel holding glass and carefully mark orientation of shaft (when nedle pulled it will shift a little) The needle is pushed on and you need to pry (straight!) up and off. For mine I used a 'V' shaped trim puller. The most time consuming part of process (for me) was reseting the odo miles on donor speedo to keep correct with records.

With needle marked you can get close to correct calibration. To get as close as possible without having to send out and pay to have calibrated I first:

Made sure battery operated drill fully charged and noted what speed was when attached to speedo.

Changed needle (above)

Used drill to see if correct. I had to reset needle once to get correct speed reading I started with drill.

The needle should just rest on the stop at zeor mph. When needle is installed if it 'floats' off the stop accuracy is off (easy to tell) If it is heavy on the stop it is more difficult to see/tell ( why I took readings with drill)

Reassemble, install, and followed pace car at different speeds to see how close I got. Mine ended up within 1 mph at speeds from 20 - 85 mph.

While speedo is apart is a good time to clean regrease worm gears and drives. Be careful not to bend/beak shaft and you should do well. Hope this helps.

The new one is electric but hopefully most of the rest will apply.

Thanks

OK I got both speedos in front of me. Changing the needles doesn't look like to much a a chore. BUT!!! How do I get the glass cover off?

Oh also I broke one of the little connectors that the buble goes into for the back light. Where can I get new ones. Mainly the part that connect to the wire and the spring.

you're gonna need a small flat screw driver or maybe a small pick to slowly remove the black brim on the gauge. Flip the gauge on it's back and you see how the factory nicely folded over the edge of the brim. Just undo what the factory did. Some gauges came w/ plastic or glass faces.

Thanks I kinda knew thats what I had to do but just wanted to make sure before I screw it up.

Brand new gauge though how freaking cool Now I just got to hope I don't royaly screw up.

While you're at it, compare the ring that you're prying off to your other one. The earlier gauges with the silver button had a deep dish ring, vs. a shallow one on the later ones. Also, the earlier gauges had glass lens, vs. plastic on the later ones. You can mix and match to come up with the combination that matches the other gauges in your cluster. Looks like you've got to keep the lens from the new one though, because of the reset button.

Prying that ring off is a pain, but it you take it slow, it'll come off and be reuseable. You've pretty much got to pry it up all the way around, not just on one side.

Good luck!

Jim

here's how...

Goddam it

Well ya know I just am not gentle enough and kinda screwed the whole thing up.

Well I got the 2 speedos apart. Which by the way putting the bezel back on is not so easy but doable.

Where my trouble started was the newer gauge has a much skinnier post that the needle goes onto. So I figured I could use the base of the newer needle and attach the old metal 914 needle to it.

As you can tell I obviously screwed that up. In the process of prying that apart I royaly screwed up the nice 914 needle. To make matters worse with the metal cap on it touches the glass.

Well I know when I need a professional and it's time to call PAspeedo. Have them set the needle right and I was gonna have them redo my tach anyways and make me a triple gauge.

I got beat this time 914

Don't feel bad you probably won't do your own surgery's eather, but at least

you tried.