timing cover leak versus top cover leak
Using the (odd) terminology from the factory service manual, the cover you must remove and reseal when doing the head is the "top cover", the one in front of the camshaft. The "timing cover" is farther down the front of the engine, and requires a whole bunch of extra stuff be stripped off the front of the engine to get to it and remove it (remove radiator, fan bearing bracket, crankshaft pulley, alternator, and a bunch more). It definitely isn't part of a normal cylinder head R&R on a 103. I know because I was in the process of a normal cylinder head R&R when I accidentally busted a timing chain guide rail and had to take the whole detour to pull the timing cover to fix that. As far as whether its "top cover" or "timing cover" leaks the 103's are notorious for, I couldn't tell you. Mine both "seeped" a tiny bit before I had to do my timing cover, and they still "seep" a little bit now.