You can down load NEMA MG1 Std( paying for it) at GlobalEngineering Documents.com
Any way, NEMA LR Code "G" means the motor will demand between 5.6 to 6.3 kVA per each motor nameplate HP.
for instance 10 HP motor, 460 VOLTS will have while starting:
kVAmin = 5.6x10 = 56 kVA
kVAmax = 6.3x10 = 63 kVA
at 460 Volts the current will be:
Inrush min = 56X1000 /(1.732x460) = 70.28 Amperes
Inrush max = 63x1000 /(1.732x460) = 79.07 Amperes
Mounting F1 is in the same NEMA MG1 Std and only means a motor Horizontal with feet (or floor mounting) with the conduit box or connection box located to the left side when loking the motor at the driving end.