I debated back and forth between using the stock cowl-attach hinges or quarter-turn fasteners and I decided to proceed with the hinges. I like the clean look and the simplicity of the hinges.
I’m planning on using a 1/8″ stainless steel hinge pin for the top hinges but with an added taper to help around the bend. I’m also planning on forming a finger-sized ring on the end of each pin to make them easy to pull without tools (I saw this idea on another RV-10).
I first made the shims then cut the hinges to length.
I pre-bent the hinges for the upper firewall then match-drilled the spacers and hinges.
I opted not to use hinges along the bottom as these are known to break over time. I instead made same-sized plates from .063. I will use nutplates and screws here.