[unruhjonny]

I have these two adapters here;
There are not the more common (at least more common type I have seen) which are the compact rectangular ones which seems to have a built in cable(?);
I am guessing that these ones require a speedo cable which is longer than the cable housing - is this correct?



It's either that, or I need something else to connect the speedo cable from my car to the gear in my transmission.

Can anyone confirm what I need to do to use these?

I am incline to use the longer of the two at a later point, because it would allow me to run all the factory stuff for my (3.55:1 geared) car, but run a 3.90:1 gear set;
At least that's how my math works out.

3.90 x 0.909 = 3.55

This one (the longer of the two) has the following stamped on one of the circular end faces:
6476884
1:0.909
005 (upside down and small "M") 2

The other one has the following stamped on BOTH of the flat circular end faces:
1565210
1:0.866
043C1

Thanks in advance for helping me out!!