Help me modding my UK D8

Hello,
I am a newbie in this forum and in the modding world.
But after I've seen all the great projects people do on this site(lovecpf) I started thinking on what can I do with my diving light - UK D8.










Now it runs originally on 8 NimH D-size cells pack and 2 * 9.6v bi-pin bulb (15w).

I thought of changing the battery into 3s2p 18650 pack for first.


Now, what Ideas can you give me for the light source, I thought of making it
5*cree or 2*sst-50 set.

What do you think? What ideas can you give me?

thanks,
yan.