Custom fab'd light bases from scratch....anyone?

[Mr MaGoo]

Hey all, am going to start drawing up some plans for my "Electrified Water" vessel.   Has anyone had to build a custom light enclosure for a project before. I have seen a video on YouTube where the guy built a small one for a smaller lamp that looked pretty good.  Let me see what you all have done!  Thanks for any info 
in advance.