Match-drill and upsize firewall and side skin connecting holes

The 3.3mm holes running down the sides of the firewall match reasonably between the firewall, side skins and the cowling strips, with mismatches up to 0.5mm only. However these holes are pretty mangled after repeated clecoing. So I decided to sweep away all the wear and tear, and the misalignments by upsizing to 4.1mm, to accept 4mm rivets

However the mismatch of the 4mm holes between the side skin and the firewall was worse, but not so bad that upsizing to 4.8mm would not clear most of the error away. The mismatch with the cowling strips was far worse, but this will be dealt with separately.

Overall view, LH side

Overall view, RH side