bearing noise (knocking) cold start

[josamkay]

My Question is can I Change the main and rod bearings with just the removel of the oil pan or is there not enough clearance for removal??? Do I need to raise the motor?? It's a 1996 305 vortec motor and its 4x4 also can i put 350 heads on this motor as long as their vortec heads?

[maxwedge]

What year is this?? Usually you have to disconnect the motor mounts and get the engine up as far as possible, oil pick up clearance can be a problem.