I can't see what is going on without pictures but from Hall's website it appears that the caliper end of the kit is using an inverted flare fitting to attach the hose to the caliper.
I will have to look at my setup but I think the original Pantera connection uses a fluid bolt and a brass block. That one uses a pair of copper crush washers.
You may need to swap in a copper crush washer under the inverted flair fitting? That will stop the leak but I'm not sure that should why they supplied an inverted flair there? The "girls" are not good at all with these kinds of details these days.
I believe that when I converted mine, I salvaged the brass block and fluid bolt design, cut out the rubber hose connection, drilled out and installed a 1/8npt to -3 adapter (steel) (or -4, don't remember which one at this writing), then used the original brass block/fluid bolt. crush washers.
Post some pictures and I can help more.
You can message me on Facebook too if that is more convenient? AKA Doug Waschenko.