94 Taurus GL & '99 Stang Prem Sound Sys

 Hi I installed a '99 Stang Prem sound system w/ cd changer & amp in my '94 Taurus. It works well except that I can't get the indash radio controls to work w/ the stang radio. The plug connection is there in the back of the HU. The only difference w/ the Stang HU is that it has a clock where the HU for a Taurus does not. Also there is a connector plug on the back of the Stang HU that has a factory installed block plug that can be removed, The same plug is on the back of the Taurus Prem HU but it is not blocked, Don't know what that connecting plug would be for. I just want to get the dash controls to work with this HU, Its all ford???  Does any one have any back panel info on the Ford Prem Sound HU's or any Ideas?

Thanks