Fuel rail has to come off to access the intake bolts... just had mine off 2 weekends ago.
Remove the beauty cover, relieve the fuel rail pressure with the service port, remove the 2 fuel line quick disconnects. Remove all the wiring to the injectors and ignition modules. Move the purge line out of the way. Remove the 4 bolts holding the fuel rail down. Pull straight up to remove the injectors from the manifold, leaving them attached to the rail. Remove all the hoses from the throttle body and intake (don't forget the HVAC vacuum line out the back end of the manifold), pull the PCV pipe out of the valve, can't access the end from the manifold.
Remove the 3 TB bolts and remove the intake manifold bolts. Remove the manifold and there's your starter.
Reassembly is the reverse. Oil the injector orings lightly with engine oil before installing the rail. You might want to have intake seals and a TB gasket on hand. Also a good time to really clean the TB. And look at your plenum for cracking.... and replace the PCV hoses and valve.
The thread is 5.5 years dead. Please Google "cadillac forums northstar starter motor replacement". Many, many threads and posts on this in here, Deville, Engines; Northstar, and Tech Tips forums.
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