I've been too tired and too distracted lately to get things done in a fast manner so I took off today so I can get my Onas ARF version close to ready to fly by the end of the weekend.
Last night I started the firewall and I thought I'd post some pics of the progress. All this took me about 4 hours. I'm not the fastest nor the slowest but I have learned to be patient and only work on critical things when your in the right frame of mind. Working on planes when it's strictly a chore tends to lead to sloppy work that hurts you in the end and causes rework.

The material for the firewall is 1/4" liteply. I laminated it with carbon fiber cloth. I've selected the AXI F3A outrunner. for installation and will be starting off with a Himas 6330 F3A new on the market.
The Himax is supposed to compare well with a Plettenburg Evo 30. I have 2 Himax mototrs now so I'm putting my faith into the reports that they are very stout and are showing excellent numbers. The motor is 2 ounces lighter than the AXI and sells for about $250. I will have this paired up with the new Castle HV80 Ice to start. The reason I'm using the AXI for mounting puposes is that it is a bit longer than the Himax and by doing this I will only need a washer to allow the Himax mounting and can then go back to an AXI if I deem necessary.
The Himax has a hole configuration that allows both the AXI and a Pletty so I will drill all 7 4mm holes so I can even put a Pletty in if I want to. The Pletty Evo's are the standard bearer outrunners for F3A and I had one last year in my Fatboy/Sickle. I choose not to continue with one because of cost. I get a kick out of doing E. pattern with a budget in mind. It gives me the ability to show others that this deal is not that expensive and it can be done inexpensivly. Heck the setup I had in my Integral at the 2008 Nats had an AXI F3A that I bought from a friend for $140 and an CC HV85 Esc that I got used for $120. So all up I had a $260 powerplant that was way more power than the plane needed and was always reliable.
The firewall is fixed into the fuse and the motors has to come out thru the nose. I secure then in with Gorilla glue that I put into a disposable glue syringe. I then spray a touch of H²o on it and let here dry. I transfer the hole pattern to the firewall using a piece of card stock it get tack glued to the motor back and the holes located then I tack that to the firewall once in place and remove the motor side. From there you drill the 4MM holes into the firewall and Bam!!!! It fits perfect.
I have a template for the firewall I'll scan and post.
The firewall installed weighs 38 grams.