You would need a 1/4 inch 12 point socket to remove the five cap bolts. AND some if not all will break, leaving you the nasty job of getting them out. The center seal on the cap needs an O-ring, a scraper ring, and a top retainer. The retainer needs to be staked in. Usually, unless the trim cylinder is very clean, it will be corroded around the retainer making it difficult to secure the new one.
Plus,most times the two shafts are corroded into the transom clamps, trim cylinder assembly, and the upper engine swivel. Really a nasty job to disassemble if you snap screws and need to drill them.. Count yourself lucky if it doesn't fight you.
Right now I have three assemblies sitting in the garage waiting for repairs, at least one which needs the screws drilled and tapped. Do NOT re-use the cap screws They have been stressed and may fail later on.