Advantages of this kit is: You can reuse half of the Catalina kit. Frame, Engine, bumpers.
Disadvantages are: You would need to do a new body and interior.
Selling Point: It's never been done before in 1/25 (I think). First year for the Grand Prix. A very few came with the 421 SD engine.
Of course if you could figure out a way to make the side chrome spear and rear trunk trim separate parts you would not need a new body, just interior, chrome tree, and those 8 lug wheels.
Just a thought! I'd get a couple so...