OK...it has been the project from heck! After 22 years, the pool lights started tripping the GFCI. I read that you should first check/replace the GFCI since it is a quick/cheap/easy fix to start with. Well, that was not the problem. So I ordered new LED bulbs (converting from old halogen), new gaskets and new tension rings (they are Pentair Amerlites). I checked that all worked without tripping before I reinstalled. However, after instalation the GFCI was tripping. I removed the lights and they all had water in them. Not sure if it is coming from lense or from back/wire-side as some of the epoxy in the back seems either cracked or slightly seperated from housing. All the ideos I watched made this look easy...not so much for a 22 year old pool with hard water 
So, now I am thinking about scrapping the 120v and switching to 12v. I found some on Amazon that have a transformer. Question is: can I simply replace the old 120's with the new 12v and put the transformers right above the j-boxes, or do I also need to pull the wires from the j-boxes up to where the pool equipment and fuse box is?
Also, any ideas what could have causedd the water in the existing lights AFTER I replaced the gaskets and rings?
TIA
Chris
So, now I am thinking about scrapping the 120v and switching to 12v. I found some on Amazon that have a transformer. Question is: can I simply replace the old 120's with the new 12v and put the transformers right above the j-boxes, or do I also need to pull the wires from the j-boxes up to where the pool equipment and fuse box is?
Also, any ideas what could have causedd the water in the existing lights AFTER I replaced the gaskets and rings?
TIA
Chris