Drill out firewall to stiffener rivet as per OP-28, position and clamp gascolator bracket to stiffeners. Drill the #30 hole on the bracket at the drilled out stiffener rivet location and cleco. Match drilled about three rivet holes (at both ends of the bracket) using the pre-drilled holes on the bracket and clecoed the bracket to the firewall. Match drill all the other rivet holes using the pre-drilled holes on the barcket. The 5 stiffener holes were drilled using #30 bits as per plans. Cleco gascolator Bracket to firewall. This was a slow and tedious job, but came out really good.
