can the 2003 SSEI eng setup be tilted forward to get at the back plugs?

You could remove the front mount and tip it down, but there is no need to do this. I changed the back plugs on mine many times without tilting the engine. First thing to do is remove the engine lift hook from the rear driver'* side to increase access to the plugs on that side.

I think its 2ea 13mm bolts for the engine lift bracket. Remove it and throw it in the tool box.

I don't know why you need to tilt the engine. Can you post a picture?

maybe he saw something about tilting the engine. the w-body is the only ones that tilt, not h like your bonnie. should be enough room without it on that

yea I did see something about it a while ago.undo motor mount and pull it forward and bolt it.

w-bodies(cutlass supreme,GP, monte, lumina,etc..) only, not your car.

I don't see why you couldn't remove the front mount (the one that goes to the radiatiator X member) on a Bonneville and tip the engine forward a little, but as I said earlier in this thread, it is not necessary to do so to change the plugs. I used to place a couple pieces of cardboard over the engine and lay on top to get at the back plugs. Once you remove the rear motor lift bracket they aren't that hard to get at.