trinary fitting 10mx1.5 for fans

[homemade87]

I did my swap a couple years ago and decided to do a engine change to a ls2. In the process I had learned that a trinary switch will control the fans. I am wanting to put it in line on the high pressure side but I cant seem the find a fitting of any kind. Doc blocks is no longer around and my searched have not come up with anything. The factory 04 switch I got with the truck is a 10mx1.5 thread and I need to add a service port in line some how. What are some of you doing for this install. Do you know of a company that has what I need. Thanks