Began assembly and riveting of the horizontal stabilizer assembly. Started to get into some corners where rivets, bucking bars, and squeezers don't like to fit or cooperate. Luckily no major sheetmetal damage. The minor scrapes will have to be buffed out and re-primed, but ended up learning a lot about making metal fit together. Also had to adjust a couple rivet sizes as the recommended size seemed too small. I'll try to have these rivets inspected before I close them up inside the read spar.