Sorry, let me rephrase what I meant to say
Follow the red jag >>> past the imax >>> along that narrow road>>> as it turns left to go to the warehouse. DO NOT turn left into the warehouse. Hang about around that general area and when the fast countdown begins (between the 6th and 7th) go into the warehouse bit. It should then say mission failed. If you do it too early then it will just continue with the next part of the mission.
If you do it right then when it says mission failed, press restart and the red jag should stop infront of you from where the chase scene began.
Hope I explained it right