Working in sections, the dry grout was packed into the joint lines, then the excess was vacuumed off the top of the bricks and gently wiped clean with sponges. Once the bricks were fairly clean, I sprayed water over the dry mix using an HPLV sprayer to start the hydration process. We worked from one end to the other in this manner, taking an entire day to do the pathway. I gave the pathway a few more sprayings of water over the next few days, letting the grout set up. Then it required about a dozen moppings to remove the haze of grout that was all over the rough-textured surface (I had put two coats of AFM Mexeseal on the bricks before starting the grouting process, but it didn't seem to help that much). After alot of scrubbing, here's the nearly finished product:
The grout was VERY slow to harden using this method, and required some touch up in certain places where there didn't seem to be enough Portland in the mix for it to set. I changed the sand/Portland ratio to 2:1 for the touch up work and this seemed to be much better...more lessons learned on the rocky road of barn-building.