Need advice on smooth fire wall, brakes, and other misc.

[protouring66]

So i guess i am kinda new here, been a shadow stalker for awhile and I love the site but haven't had much to offer so i didn't post much. I need help with some custom work i am about to undertake on my car and i posted for info on team chevelle too. But here it goes:

So feel free to laugh or whatever, but I am going to be tearing into my 66 chevelle over this winter, finally got my 63 belair into the ranks of nice daily driver. time to start on my dream ride, lol. Anyway many of you may remember an amazing 67 chevelle that was at sema last year and it had a shaved fire wall that was stunning, completely smooth with a rolled edge, 90 degree reversed brake master and clutch under the dash and everything looked perfect. i want something similar.

I know it wont be the same and i don't want to copy anyone. I am not afraid to do the work, and have a few resources for metal fab that will save me a lot of time, money, and get me some nice 1 off pieces. But my lack of experience is kicking here, I have done wire tucks, and other nice touches to my other cars but a shaved fire wall is something i have never tackled. my question is this basically because on my belair the previous owner smashed a dent into the firewall to fit an HEI distributor in with the 327 in place of the original 6 cyl. It looked bad so i cut it out, made a "cup" to put back in its place, welded it in and looks better, like it belongs there, but i don't want that on my chevelle. Will there be clearance issues if the fire wall is shaved? Super Chevy did an article on an overlay style panel that makes it look easy but what about clearance?

If I shave the fire wall and want to get it right the first time without cutting out and moving a half dozen times, should it be moved back say 2 inches? Would that allow more clearance? Is it necessary to acheive what I am looking for? Also i am going to be putting in a 572 fuel injected bbc, so what kind of clearance is needed for it? I couldn't find much info about this so I wanted to ask. I also wanted know if anyone has used the Kugel 90degree reversed brake and clutch system? Whats your input? And what about the heater core? where does everyone put the lines for it? Looks like i could put them farther right and down lower into the fender well or even into the area where the firewall starts to bend back to the floor with some custom lines and heater core.

I am building this to be driven, so my girl and I can take it anywhere, heat and ac are a must on this car. Its going to be an on going project so I know it won't be done over the winter. But fab work and metal are where I am starting.

Also while its down and apart my frame is getting redone from front to back, cross braced, notched and I am mini tubbing the car to clear wider tires, much of the floor is going to be modified, is it possible to do a flat/smooth floor in the car instead of buying floor pans and chopping them up or am i missing something as to why all the contours to the floor? (and i mean besides the trans tunnel and seat mounts) i mean i have to change some stuff to put in the new GTO seats front and rear anyway.

sorry for the long winded post but just some stuff i have been needed answers to for a while, thanks guys