Speedo wiring and recalibration

I'm putting the engine/trans from a '86 560SEL into my '72 350SL. My '72 speedo used cable drive, but the '86 trans has no cable gearing, just what looks like a Hall effect sender.

I've ordered a used speedo from a 560SL (so it will fit in my SL's gauge cluster), but I don't know what wiring is needed to connect the Hall effect sender in the trans to the 560SL speedo.

Once I get it wired correctly, I'll also need to know how it can be recalibrated since my rear end ratio is 3.07:1 rather than the 2.47:1 that was in the car the transmission came from.

Thanks in advance,
M D Nugent
Renton, WA

[joe p]

www.isspro.com, I talked with these guys a while back, they seemed to understand reprograming electronic speedo's.


Joe

First, thanks for the referral to the speedo shop - I emailed them for a quote to recalibrate but haven't heard back yet.

Now that I have the 560SL speedo, I need to know what gets connected to it (then I'll figure out if my '72 SL has all those things!). This is what the backside looks like:


For those who didn't remember from earlier in the thread, I'm putting a 560SEL engine/trans in my SL, so I have to use a speedo that uses the same type of sender the (newer)transmission has.

Thanks,
M D Nugent