1979 F250 Custom, Need help with Speedo Cable Install
 

So it is no surprise to me that my speedometer cable broke, she's an old girl.
I bought a new cable and this morning I went to go pull the old one and install the new one.

The new cable is plugged into the back of my dash already, but I have not reassembled completely yet due to running into a bit of a snag.

I watched to get an idea of how to go about replacing this cable since I had never done it before. Simple. I thought it was gonna take me 10 minutes, maybe 30 because I am new to this whole thing. WRONG!!! I ran into something that it seems has TWO speedometer cables plugged into it. I need some help. Should I just bypass this part or try and continue to use it?

It has one cable from the transmission and another from the dash.

I bypassed it and the only problem I have had is that my new cable has SO much slack that it moved against the exhaust and melted. I could see my speed for about 20 minutes of driving. Haha, back to square one, waiting for AutoZone to get the new cable in and then running it in a new path. :(

The dual cable S/B for a cruise control transducer. Old Uhaul trucks used to have a 'speed limiter' transducer run off the two piece speedo cable that measured rotatio speed,, and throttle limiting would then be under control with a throttle position/limiting governor.

Sometimes the aftermarket parts aren't to spec as OE. Yeah, nothing more disapointing than doing a job twice..