Here is my build

If you need some caliper brackets, the Chevy 70's or 80's disc brake calipers work very well for most swaps. Depending on whether you got 70's std. or 80's metric, Speedway sells brackets that I've use numerous times for disc brake swaps. They are for 3" axle weld on, but I cut them to fit the spindles, and then drill them to bolt on. $10 ea., so easier than making them too!
I trace them on cardboard, and then cut the cardboard to fit the spindle. Then transfer that back to the bracket to trace where to remove metal. Once bolted on with two bolts, I cut steel and weld it on to get the 3rd bolt hole. These are the brackets:

https://www.speedwaymotors.com/Weld-On-1969-77-GM-Flat-Mount-Caliper-Bracket,3348.html

I like the box tubing framework on your floor! Looks great!

When I saw the first image with closed edge out I said, "That's the one I like!"
Then I saw it with the open edge out, and I liked it better. Only thing I'd add is nice rounded corners on the risers.
I guess my decision would be based on whether I planned to use the area under the seats for any storage, a radio, or??? If no plans for storage space, then I'd leave the open edge out.

Coming along nicely!

The wheelbarrow firewall thing is great for most small block V* engines. But usually wont have enough width to use with a big block engine setup, regardless of maker. When I did my Austin with a SBC I went to the hardware store to measure wheelbarrows, and compared it to my firewall. It wasn't much smaller than my firewall, and I decided I'd be better off cutting my whole firewall out and simply making it flat with a small recess for distributor maintenance and clearance.

Both of my cars were as much used swap meet or CL parts as possible. Just can't bring myself to buy a bunch of new parts when good used parts work.

Nice work! I use heims also for steering shaft support.

Great looking Stude pickup!

Hit the throttle when the last yellow lights up, and you'll cut down those reaction times by a bunch. Might on rare occasion red light, but mostly it will just get your times down in the .010 or so times.

When I made my first return trip to the drags after over 30 years away, my reaction times were in the .5 to .8 sec. times! Then a friend gave me the same advice to hit the pedal on the last yellow, and instantly my reaction times improved a lot.

My local track is prepped, but I never run at it due to their restrictive rules. The track I run at is not prepped, and being near Mt. St. Helens it can often have a thin powdering of ash dust, which can really make things dicey when you hit that first shift!

I built my tilt front end with a toggle link system just so it was easy to tilt the steel clip by myself.

I run both of my trans coolers flat under the radiators so they don't block any air flow to the radiator, but aren't up high where all the heat rises. I'd move your cooler below the radiator in a horizontal position where it gets a lot more cool air. Just my thoughts on it.