I decided to switch from my weldless fittings on my keggles to welded 1/2" stainless steel couplers. Initially, I had one weldless fitting on both kegs. When I moved to welded couplers, I decided to add one more coupler close to the top of each keg for a return.
I have QDs from McMaster that will be screwed into the couplers so changing hoses will be quick and easy when using my new march pump.
I enlisted GreenMonti to do the welding after seeing his welding skills in Welding questions
. He also drilled the new holes (as I don't have tools at my apartment) and plasma cut the top off of a third keg I am having him convert. The top will then have washers welded onto it so it can be used as a lid on the HLT.
Here are a few of the first pictures of the kegs: