That's a great idea, Suhaib! Rather than discard parts that you don't need...simply buy the chassis, and add on the the parts that you do need.
On the subject of the Buggy vs Rat Rod, let's do a small analysis of the work both would require...
Buggy
a. V8, 4wd gearbox, and transfer case. With a requirement of greater low end torque (e.g., 2UZ)
b. Suspension lift.
c. Big tyres, rims, beadlocks.
d. Roll cage.
Rat Rod
a. V8, RWD, no need for transfer case. Perfect for a 1UZ with its bolt-on Tiptronic transmission.
b. Suspension drop. Channeled body. Shaved roof.
c. Car tires...not necessarily monstrously large, or outrageously expensive. Perhaps slicks at the rears.
d. Roll cage can be dispensed with.
That way, it's my belief that building a rat rod might be actually cheaper and easier than building a Baja Buggy / rock crawler. And waisey bhi, Boss...with the FZJ79, the Phantom, and the RR, I'm actually NOT looking to build an extreme off-roader. Just something that would be a nice, novel project.