[John1964]

2002 3800. One of my underwater lights is blowing its fuse. Upon examination I found a 6 amp fuse blown. I tried a 10 amp which immediately blew. So, I assume something is wrong with the light. Next bottom job I would like to have a couple of new ones on hand so I would appreciate some recommendations what to buy. When I bought the boat six months ago I did not notice the brand currently on the boat.

Replacing the fuse with a higher amperage one is asking for serious electrical issues and possibly causing a fire.  You could fry your system from the fuse to the point of use.  

A fuse box is installed for electrical distribution, but more importantly for safety.  Upon investigation, your insurance won't cover you for intentionally overriding your rated fuse.