As someone who's broken their frame in half more than a couple times....
You are correct, that overly notched!
OP, you need to add more back or a bridge on top.
An update on the truck: The exhaust headers have been modified to allow the steering shaft to split the tubes and ride between them on the driver side and go straight back on the passenger side, The front suspension is all fitted up and the motor mounts are positioned and welded in. The guy was bending the brake lines while I was there dropping off a set of corvette wheels and tires.
^ When I was selling exhaust I met a few of those guys who were artists with their Huth and Bendpak machines.
So... looks like he re-worked a set of Hedmans?
The "C" notch doesn't bother me as much as the boxing on the cross member. This looks curved like it's 18ga and not 3/16 or 1/8th. Maybe an optical illusion. I have those all the time. LOL. Just an observation from the peanut gallery. Love the build.
Zim