I thought about that but for me that isn't desirable or practical, I want the lines protected and accessible. Unlike so many these days, I am not a fan of smoothed out firewalls, hidden lines and wires. On my 70 challenger RT I have the Holley HP ECU in the drivers side fenderwell up above the brace, it was the only place I could find that I liked to mount it.I blocked off the majority of the holes on my firewall too. Planning on routing between inner and out fenders.
Sounds like you got this pretty well sorted out. I am sure it will be nice when finished.My wall will still be lumps and bumps, just minus many holes. Hoses and wiring will be shielded from debris, ECM will be inside passenger compartment. Since I'm using a 70 k-frame in my 65, it moved the engine/trans back 1.5". The a/c plumbing and expansion valve were right in the middle of the wall, already close to the engine before it got moved back. Had to get moved anyway.
Mine will be here Friday, unfortunately it will be quite a while before I can use