I am going to plate the section taken out and install a flat plate to the inner part of the rail. More than likely I will also install a 1x2 rect tubing(or something similar) between the rails for added support. I will probably over-engineer it but, better safe than sorry. I am picking up all of the metal to make the plates and stiffeners tomorrow and hopefully going to have one side done this week. I need to decide on weather to make my old tub fit or just bite the bullet and order a set of the DSE deep tubs.
I saw a set of the DSE tubs at a Goodguys show a while back. When my car gets redone in a couple more years' I plan on a set of those for mine. They look awsome. They had them splatter painted if you didn't know the difference you couldn't tell they were installed. It was a slick setup.
I notched the frame rails on my '67 when I re-mini tubbed. I used 1/8" plate. I have coil over shocks so the upper mounting bar goes in between the frame rails and the back tubes of the roll bar attach to the frame. So I dont think there is any structure sacrifice.
how rusty/rotted are those frame rails? im only asking because my car has holes in the spot that you cut out and theyre caving in a little in some places. im getting ready for a new 9 inch rearend this winter as well as putting in my caltracs, the smith racecraft rear suspension, fuel cell, and 6 pt. i was planning on putting in replacement frame rails from comp engineering or S&W but if i could possibly save the rails i have it would save me some money. dont know if this would be a good idea or not. on top of it all my sister backed into my car a few weeks back and kinked one frame rail and wrinkled my quarter pretty good so it has to be pulled now. i like how you knotched into the frame rail for more clearance but i dont know if my rails are too far gone to do that and keep structural integrity. i could prob weld plates to stiffen them but i dont want it to look hack or get too heavy. prob gonna buy rails but just wondering what condition your rails were in.
The rails are in very good shape and not real rusty at all. I an goingto plate the back side and the notch with 3/16 plate and tube between the rails. I sorta feel that it will possibly be stronger than stock by the time I am done (hopefully!)