Best to apply some free me up stuff. I actually loosen them up a little-each one-and then spray lube between the manifold and block to allow it to creep up the threads. Then if they’re tight I work them back and forth. But if they’re loose, I just take out the middles first. Use an air ratchet.
Going back in-I clean the threads on a wire wheel and apply anti seize on the threads. Use a torque wrench. Upload a picture or 2.
Looks like the passenger side is a breeze-Famous last words.