I ran into the same problem, and I remember thinking the same things as you.

I ended up drilling a 1/2" hole between the two dowel rod holes, so I could see from the outside while I had my hand inside. I also removed the long shelf with the holes in it, and built a light framework to it for the batteries on top, and the receiver underneath (or vice-versa, can't remember exactly). Once I had all of them secured to it, I put it back in and glued it down again. It helped to keep the weight forward for the balance. I installed the Syssa 30CC on mine, which I think is pretty close in weight to the DLE 30. The problem I had with preparing the firewall for my Syssa was that my mount points were far enough apart that I ended up having fight the tri-stocks out by the sides, where the outside of your added bracing butts up against it. I didn't have to fight with the plywood the tri-stock was glued to. The tri-stock was enough trouble by itself! Finally got it. THAT was a job. I'd definitely do something more like what you've done here if I was building another S-Stearman. Looking at your photos here, I see it's MUCH easier to bring the firewall up higher on the tri-stock than to carve the tri-stock down to the firewall. I used some tri-stock epoxied in on the outside edges, but the carbon fiber looks quick and easy. I'm building an RC Guys Super Decathlon right now, and looking at some rather tight corners that I want to reinforce. Maybe the Carbon Fiber is the way to go. Thanks for the idea!

Looks like you're doing a nice job, Mick.

Keep those photos coming!

~ Jim ~[8D]