Yes. Otherwise they can leak. Also the 2 that hold the power steering pump bracket onto the timing cover are in the water jacket. They can leak as well
I just finished a Magnum build and had a leak at the timing cover bolt behind the lower hose water pump connection. Had to pull the WP off to fix. Also an AC car so that added to the joy. Bolt had sealant but apparently not enough. Luckily I only had water in the system for first fire.
