That's an early model MC1 drive. If it's been tied up like that for 5 years, you have a heap of work to do before you go anywhere near the water. First, replace the uni bellows, split the drive and do the water pump impeller as a minimum. Check the alignment, grease the unis and gimbal bearing, if their condition checks out ok, if not replace them. check all the shift mechanism and the shift cable and it's bellows... A full engine check, then oil and filters change, full tune-up including new plugs, points, condensor, rotor, plug leads and distributor cap. Thoroughly check the exhaust manifold and elbow (with a view to replacing the elbow).... Pull the fuel pump and carburettor off and clean the crud out of them and set the carb up according to the book (not a seloc or clymer :facepalm:, the proper genuine workshop manual). Also clean all the fuel lines, and drain the have the fuel tank steam cleaned (on the inside).... And we haven't even started on the electrical system yet....
Good luck.
Chris.......