how far can you rock the engine forward without breaking something?

 

Rotate the engine forward far enough for the second (unused hole) in the dog bone to line up with the one you pulled the bolt out of. Then insert the bolt you took out into that hole to hold the engine in place instead of using a strap. Also loosen the other bolts that pass through the rubber bushings so you don't tear the bushings when you pivot the dog bone.
The book also says to have the transmission in neutral when you rotate the engine forward, I suppose so there is no strain and/or resistance on/or from the transmission. Use ACDelco Irridium or NGK Platinum plugs. Definitely not Bosch.

 

Can you change the rear sparks plugs while the car is up on the lift? A mechanic says you reach them easily. If so, I'll change the rear plugs next oil change.

 

I noticed when helping my neighbor with his 3800 monte it was next to a pita to go from the bottom. but doing it from the top to me is a little easier than bottom. but with some negotiating skills but not that pita as some think. once you do it the first time you end up making notes on the best way to get to the plugs for each one in the back

 

No reason to bother with all that mess. If you don't think there is enough room, undo the dogbones and rock the engine forward. It's 2 simple bolts, doubles your space, and puts them at an easier angle.

 

I've always done the plugs from up top and never had to move the engine. But that's me