Yes, I did as advised. It worked good, no problems. But I used only clecos so far.
Yes, that was a problem in my built to. At first I was wondering why the firewall would bent at 1/3 height. Then I saw the angles you mentioned. So I removed the firewall completly and clecoed the hole firewall inside and outside on the bench.
Next step is riveting something on or around the firewall, but I'm afraid of riviting pieces and drilling out one chapter later.
For instance there are SF240 and SF241 The manual doesn't show wherer exactly to put them. Do they go betwen sidewall and firewall???
I searched Kyle's blog over and over to get hints on what comes betwen sidewalls and firewall. But I'm not sure.