Terminology might help. Your brake system uses "inverted flares". The "through the frame" type of fittings are usually called "bulkhead" fittings. Your old truck uses standard threads. If you are looking to cross over to late model parts, stick with the late 1970's parts and earlier so that you don't mix any metric stuff in there. The only "T" with a hose attached, you will mostly find for rear axle applications.
I recently built my brake system. Using old Wagner parts catalogs, I put together what I needed. At least for the hoses I needed. Some "T"s came from Summitracing.com. I think some inverted flare nuts came from Summit.
