68 BB motor mount ???

[Tinkerr]

Does anybody know when GM went to the motor mounts with the safety feature and eliminated the safety strap.  For a 68 Camaro GM lists #3990914  without the safety design. If you go to Napa their book call for #6021107 which crosses to GM #3962748 which has the safety design. I don't know which is correct. Any ideas???