Ok, on the process you've listed for mounting the new buckets is spot on. As the saying goes, " measure twice, cut once." I would recommend welding the inner seat brackets.
On the console, does the one you are getting look like mine?
View attachment 61411
I used the mounts i cut from the same donor monte i got the console. The aftermarket mounts will work, should be a long mount, then a small mount for the front area. YOU DON'T NEED factory shifter mounts!!!!! Use the hurst mounting holes to locate where holes need to be drilled while the console shifter plate is out.
All i did was add some 3/16"-ish thick tubing, about an inch tall to each side of the rear shifter mounting bolts to level the shifter with the console. I then used the shifter plate as a template to notch out the factory console plate to clear the hurst shifter.