Fitting firewall plywood

Cut out the firewall to the shape drawn out on the plywood. Carefully sand it until it fits snugly in position. The front face of the plywood must be in line with the start of the cowling joggle. Remove peel ply in the area where the plywood rests. Because the fuselage is tapered towards the nose it is difficult to keep the plywood in position...to assist I drilled a few 2.5mm holes and temporarily inserted nails to help position it. Once happy that the firewall is perfectly in position mix some cotton flox and apply this to the outer edge of the plywood. I chose to only "tack" the firewall in place in this first phase. In addition to the flox I also applied a few pieces of 20mm wide 280gsm (cut at 45 deg) between the nails.  Once cured I will apply the further layers.