Note that since T-Plate Mount is double length, only the forward two T-Plate positions can be used on the chassis. (This is usually not an issue since the forward two position is enough to accommodate pretty much all bodies.)
Install the two countersunk screws to hold the T-Plate Mount onto the chassis. Do not over tight the self tapping screws, or the hole on the chassis may strip.
Fasten the T-Plate onto the holder with two machine screws. Be sure the machine screw threads protrude past the T-Plate Mount when the screws are seated. This will insure full thread engagement. Machine screws can then be torque tighter than the self tapping countersunk screws to securely fasten the T-Plate. Take care not to over torque machine screws.
It is advisable to test fit the T-Plate on the holder with the machine screws first to verify that that the machine screw threads protrudes past the holder. A minimum of 1 thread protrusion is recommended.