speed sensor adapter
 

trying to use my original gauges for my 4.0l engine but can't find the adapter that I was informed to get.

http://www.off-road.com/jeep/tech/4lswap/
"Your existing Gauges: Use the VSS and adapter from a 91 wrangler. These have the VSS needed for the computer and also a throughput for the mechanical speedometer cable.
The sensor pictured was gathered from Pirate4x4.com in a post made by “gripguru”
He provided the following part numbers:
5/8"x7/8" speedo apapter #9400012
vehicle speed sensor #56027015"

I bought the 91 speed sensor but don't know where to use this reference number for the adapter.

Any ideas?