Installed two inspection access panels in the tunnel area for the fuel pump, filter and selector. Took awhile working out the combination of tools that worked best for me to accurately cut the holes. The Tunnel Access Panel Kit from AirWard is very nice with good instructions for the installation. I had to start by removing some LP4-3 rivets from the bottom edge of the floor panel. The kit came complete with all the necessary hardware. It was recommended to me to stagger the position of the openings to allow easier access to the fuel pump and filter. The holes lined up fairly well. Just some minor match drilling. Then drilled the corners with a step drill bit. I started cutting the hole with a small pneumatic reciprocating saw then trimmed it with a die grinder with a thin metal disk. I did substitute K1100-08 nutplates for the K1000-08 nutplates, as I wanted to dimple the doubler plate for the flush rivets and MS24694S4 machine screws.