I have 2 underwater lights about 10 years old, before LED's. Have changed the little thin tube halogen, same as work lights, just about every year. I think 500w each. This year, when I pulled one of them out, however, there was a little water inside, so I must have screwed up when I put the gasket in last time and it didn't seal perfectly. Needless to say, a new bulb didn't work. Where the cables are all sealed, is it hard to replace the entire sealed unit? Is it "worth" replacing the whole sealed unit with the same technology or better to change to LED? If so, "can" I change to LED without pulling a whole new cable from the panel (inside my shed) as I've seen described before, where fancy LED units that do a whole show of colors require a whole new cable be pulled.