I would go with used oil filed pipe. Will last infinity longer than any pressure treated post or RR ties. It isn't as cheap as it once was but you will never need to replace.
I have one, basically the same as an 8274 but no power out and the brake is just a metal strap with a cork liner. Using a ford starter solenoid and a momentary switch to power it.
When I swapped in a 78 2F into my 74 FJ40 the biggest issue was that the 2F manifold put the carb and therefore the throttle linkage further to the diver's side making the linkage between the firewall and the carb not align properly. It will work ok at an angle but is not ideal. Someday I will...
I keep my toe in at 1/8" to 1/4". If everything in the front axle is new you shouldn't need a steering stabilizer. Haven't run one for 20 years since I did the spring over and rebuilt the front axle.
I have that adapter on my rig. Bought it off another member many years ago. Mine was missing the lock but and AA was able to look it up in there system and get me the parts I needed. I would just call them and ask.
Alright, before I try and make something out of aluminum or sheet metal, does anyone have an old junk Kayline/STC top that has some good sections of the K-lock plastic extrusion they would be willing to part with? LMK
just add new top mounts to the back side of the tube (instead of the front) where they mount. That's all I did when I flipped my springs and it has been working fine for years.