No Need For Vss?

[samlex]

just pulled apart my 07 yukon denali and There are four plugs on the factory cd/dvd player and all four plugs go directly into the factory nav head unit, I have to still get the radio unlocked at dealer, but it looks to me that the connector that goes where the vss harness goes is wired the same as the aftermaket harness i puchased on e-bay, the same positions on the pin out are used. I guess ill ty it without the aftermarket harness and c what happens. any chance that the factory harness already includes the vss i need for nav???

 

also it is a little nerve racking taking the pillar covers off by the airbags to get front dash apart for gps ant installation