True! Danny Bahn of DB Performance Engineering recommended a '94/'95 Mustang shifter but it requires bushings in the larger bolt holes for it to bolt to a '93 and older T-5. There's a 4 speed shift handle look-alike that costs big bucks available also from your friendly neighborhood Mustang parts places
I don't believe you have to cut your shifter hole for the shifter I know of 3 66s with 5.0s and T5s and none of them had problems with alignment of the shifter through there. If there appears to be clearance problems loosen the motor and trans mounts and align the drivetrain. There is enough play in these connections to correct any misalignment you encounter.
Tom Kubler, Long-time Mustang Enthusiast & San Antonio Mustang Club Founder