SFC's 1st without a doubt. My buddies car (00 Z) is a hardtop also and has heads/cam/spray/TC and gears. He went to put (weld on front & rear) SFC's on the car. Left side barely lined up. right side required a 1/4-3/8 wide steel spacer at the rear due to the car being twisted from racing. If the engine is healthy (read: tons o' torque) and you drag race it it will twist into a pretzel eventually.