I just snatched up a D1 Navigation unit off eBay for a little under $400. I read over the D3 install thread, but that leads me to my question: Is the D1 installation the same as the D3? I ordered the wiring harness (Metra Part #70-5521) and the Dash Kit (Metra Part #95-5812). Is there anything else I need to know for the install, particularly anything that's different from the D3 install?

I read on another forum someone having issues with the VSS, is that a concern of mine?

'05 Mustang GT w/ Shaker 500.