"G84 Z.570 R.03 F.03125 S300R1"
Normally when working on back spindle you'd need to add D2 (spindle 2) and a comma before the R1. E.g
G84 Z.570 R.03 F.03125 S300 D2, R1
However to the best of my knowledge "rigid" tapping G84 is not possible on this age of machine. Normally I'd use a sprung collet or sprung drill chuck and G32 cycle as follows
G32 Z.57 F0.03 T33 (95% of pitch on entry)
G32 Z-2.0 F.03125 M24 (100 % pitch while reversing)
G4 U1.0 (Dwell for spring)
G0 Z-0.05 T0