Oil pan change?

If your car has headers all bets are off. If it has stock iron manifolds then yes you can swap the pan gasket. The service manual for your year car will tell you how. Basically you need to drop the center link, remove the starter (I think) - loosen the motor mounts off the k frame and raise the engine a couple inches, be sure to check for clearance around the distributor when lifting the motor, also watch your fan and fan shroud for interference problems. Once up shove a couple pieces of wood (like a short 2x4's or 1x's) in between the mounts and the frame, lower the motor on to the wood and remove the pan, reinstall, and reverse the procedure. As long as you dont turn the tie rod ends nothing should change too much on your alignment. I would check your rear main seal as well, these usually leak terribly on small blocks, especially with some miles on them.