i've got a 5.4L with the plastic intake manifold, and a coupple of the darn COP screw inserts are stripped in the intake manifold and all the do is spin, i cant get the screw out, tried pulling it out with vice grips, squezeing the plastic insert houseing with vicegrips too still nothing, any tricks to getting these screws out becides cutting them out?

 

Did you try pulling them up with the visegrips and turning the visegrips counterclockwise at the same time?