This work was completed over several days and nights, just going to do one big update as opposed to breaking it down into the small chunks. The initial mock up and build up of the frame is pretty straight forward until you get to the last few parts with all the match drilling and set up required to get everything aligned and in the correct place at the forward spar junction. I cannot emphasize this enough so I will put it as its own sentence: DRAW A CENTERLINE ON ALL OF THE RIBS, ALONG THE ENTIRE LENGTH OF EACH RIB'S UPPER AND LOWER FLANGE! Thankfully I had read that tip before I started on the horizontal stabilizer and I'm glad I did as it made things much easier than it would have been otherwise. The instructions have you do this on a few pieces but don't mention doing this on all of the flanges. Since the holes that get drilled are being drilled on small flanges, edge distance is critical and being off by just 1/8 of an inch could ruin a part to the point where you may have to scrap it. So this set of days/nights was dealing with getting HS-00005 and HS-00006 in place and get their front and rear flanges match drilled to the rest of the frame. These two rib pieces are different than what was in my original kit as these are the updated parts that are a result of the SB that strengthens this part of the tail. So after a lot of reading of the instructions making sure to get everything right, it was time to start test fitting these two ribs into place on the inboard side of the stabilizer. These ribs have no pre-drilled holes in them so fitting them into the inner portion of the skin requires the use of a lot of cleco clamps or something similar. Fortunately I had plenty of these and made good use of them. The instructions have you test fit these, check for fit, check for hole alignment, etc. Then remove everything, debur, flute, etc. Long story short, you put the whole thing together and take it back apart about three or four times. Each time you work on a few holes that need to be drilled and the order is important. Follow the directions and things go together fairly easily. There was some hand wringing on a few holes knowing how tight the tolerances are but again having the centerlines drawn on the rib flanges really helped. The pictures included tell most of the stories. The bulk of the hard work is getting the front flange of HS-00005 and the rear flange of HS-00006 drilled in place with everything fitting properly. With that done, you can drill the holes for the top and bottom flanges of these two ribs using the holes in the skin as a guide which is pretty straight forward. With those crucial steps complete, you simply matchdrill the remainder of the frame using the skin holes as your guide. Once that was done, there are four holes that still need to be drilled through the two spar doublers and the HS-00003 piece. I used a printout of the plans that show this section as a guide to make sure I had all the holes drilled. The four circled holes in that picture are the ones that you have to drill and fortunately, and I can't even remember where or when, but these four holes are already drilled in the HS-00003 part. I think they are pre-drilled but either way they were already there on the back side of the piece so it was just a simple matter once again of match drilling. With that all complete, this finishes this section of the horizontal stab as far as the mock-up goes. From here you take everything apart, debur, clean and prep for paint, dimple the skin and then prime if desired. So that's one half of the stab mock-up complete. You simply repeat this process for the other side. I didn't run into too many issues during this phase, there is a single hole on the top and bottom of the skin that due to the age of my kit (2011) and the incorporation of the SB, this hole will not have a matching hole to rivet it to and therefore can be considered a blank and filled with a rivet. The SB plans direct you to do this. Next steps will be to prep and prime these parts. I think I will do that as I've yet to prime much of anything since moving the project back into the garage and this will be a nice break from the mock-up process. Although I will freely admit that prepping the parts for paint is a giant pain in the rear and probably my least favorite part of the build, just lots of manual labor that has no real short cuts to it. Look closely at the two images of the forward rib HS-00006 clamped in place. You can see the centerline that is drawn on the top of that part's flange that allows you to align the rib properly before you drill it. If you didn't have this reference line, it would make lining the rib up properly somewhat difficult. I would also recommend using the thin tip version of the Sharpie as the regular sharpie makes too thick of a line to use reliably. With all the reference lines and everything aligned and clamped in place, you can be pretty confident that when you start drilling the holes for HS-00006 and HS-00005 that everything will line up as it should and your match drilled holes will be right down the center of the flange like they should be.