Ford 1999 Mustang Owner's Manual page 129

Roadside emergencies
It is recommended that your vehicle be towed with a
wheel lift or flatbed equipment. Do not tow with a
slingbelt. Ford Motor Company has not approved a
slingbelt towing procedure.
If your vehicle is to be towed from the rear using
wheel lift equipment, the front wheels must be
placed on a dolly to prevent damage to the front
fascia (bumper).
If the vehicle is towed by other means or
incorrectly, vehicle damage may occur.
Ford Motor Company provides a towing manual for
all authorized tow truck operators. Have your tow
truck operator refer to this manual for proper
hook-up and towing procedures for your vehicle.
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