Because of the weight of the motor and the power. It WILL twist the frame the first time you punch it. If you box YOU MUST bod From the front of the arm Mounting point to the rear leaf Mounts. You will also, want a cross over bracing. Like an X frame.

Depending when the book was made. The tecnologies today require the X Frame support. It is by far safer. I do not recomend installing any wires or tubing like brake lines inside your future inclosed frame as stated in another post. If there is leaks or a short in the wires. You will have a hard time. Plus if they are installed before you box the frame. YOU may very well have issues with the heat doing damage to the wires etc.

Good luck


Poets Seat Auto
Appraisals, Parts, Service
Past: General Motor's Master Technician
Member: Northeast Chevy/GMC Truck Club
Phone Number: 413.774.5856
Collector of: 1951 Army Chevy Burb barn door,53 GMC COE,two 1934 Chevy Truck,1935 Chevy Army Truck.1950 Gmc Suburban clamshell these are just my chevy/gmc trucks.