Hi guys, I posted this in the 140-160 section but realise it is probably better here!

Just wondering if anyone has switched to electronic speedo drive (from the rear axle), in your 140's, when you switched to a later model transmission.

I see from having a look at a 240 that the sensor goes in through the cover plate on the diff, my questions are as follows:

1) Does the diff cover plate swap over between the 140 (mine is a '69 model 142 if that makes any difference) and 240's?

2) What apart from the cover plate and sensor is required to be swapped to get the speedo drive working?

3) I take it there must be something attached to the gears in the diff itself that allows the sensor to pickup some kind of signal and send it to the speedo, how exactly does the sensor work? is it magnetic?

Cheers,

Daz