Completed step 5 page 10-02 – riveted F-1208A wear plate to the F-1208-R fuselage frame per Figure 3 with LP4-3 rivets. Completed step 6 page 10-02 – clecoed then riveted F-1208L &R frames and clecoed and riveted F-1209L &R frames per Figure 3. Completed step 10 page 10-02 – riveted the F-1210A L&R frames to the F-1210B plate and F-1210C angle with AN470 AD4 rivets as shown in Figure 4 – detail AA. Rivets checked with rivet gauge – all good. Completed step 1 page 10-04 – riveted the F-1211D attach brackets together and installed bushing per Figure 1. Installed busing in F-1211D stand-alone bracket. Completed steps 7-9 page 10-04 – riveted bulkhead to bulkhead doubler F-1211D attach brackets and F-1211G tail skid bracket per Figure 2. Have one AN470AD4-4 rivet adjacent to hinge bracket bend that slipped when squeezing causing part of the manufactured head to break off. Need to look at how to remove the rivet and replace. Decided to use mill and mill off the shop head to almost flush condition. Then used center drill to start hole and the drilled through with #39 drill which broke remainder of rivet loose. Inspected rivet hole – no damage – installed new rivet and now looks great!