can anyone tell me as im outsiude right now in the dark trying...

Remove the dust cover from the flywheel. Jam something in there against the teeth or the bolts to hold the engine from turning. Use a VERY LARGE breaker bar to break the bolt loose. Probably with a pipe extension.

OR

Use an impact wrench with 500-600 ft/lbs IN REVERSE capability.

Is this on the 88 or another car? I thought pre-92 3800 slip off when you get the bolt off. But 92-up require a harmonic balancer puller. Three screws go through the puller plate and thread into the pulley holes down inside (M6x1 thread, get 75mm long or so), then you turn the center stud of the puller and that will push on a socket that you put into the bolt hole beforehand. It'll pop free eventually.

I neglected to mention the puller, as I assumed he knew that.

To get the BOLT off, he should follow my post above.

LOL..

Forgot the puller after the number of them you've done. That'* funny.

Personally..I recommend ~80-90mm long bolts to remove the pulley. Rent or buy a harmonic puller and don't expect it to have the right size bolts. Our balancers have the worlds smallest and dumbest size ever designed.

What year car is this in reference to?

I go with slightly longer bolts and use washers to set the length. M6 bolt heads may be on the small size for the slots in the puller. Depends on who makes the puller. I keep a bag of 3 bolt lenghts and several washers with my puller.

Agreed. Many spare grade 8 washers are in my puller case with the "wimpy sized" bolts.

o.k today i went to pepboys and bought a puller and a cordless impact wrench set.. is there anything i need to no as i never changed a crank sensor b4.. this will be my first..
could i ruin spomething by putting it back on too tight.. how do i no what to tight is? thanks

I seriously doubt the ability of the electric impact to do the job. Good luck. You need air tools or alot of leverage and muscle.

AND can you PLEASE tell us which car you're talking about?