ok... let me see about rephrasing this...
1. accelerate to 105 or so however you want (get to 105 MPH, it doesn't matter how)
2. let the tranny go to 4th gear and lockup (let up off the accelerator and go like your gonna cruise at 105 MPH)
3. give it enough gas to accelerate while still staying in 4th and lockup (give it a little bit more gas, enough so you start to accelerate slowly towards 108 MPH)
4. when you reach 108 or when you stop accelerating, floor it (when you get to 108 MPH, put that tall narrow pedal thingy (gas pedal) on the floor)
anything i need to clarify?