[M_RABID]

How did they ever get GMS out of GM Employee Discount?!?

I'm not going to go into the old 'Option 1 order' and 'Option 2 stock' pricing, but they were both replaced when GM set the employee discounts as fixed selling prices rather than rebate amounts to be subtracted from the selling price of the vehicle.

Option 1 became 'GMO' or GM Order. ie GM employee price for a special order vehicle. GMO was slightly lower than buying out of stock.

Option 2 became 'GMS' or GM Stock. ie GM employee price for 'out of stock' vehicles.

A few years back, GMO became the same price as GMS. Then GMO was dropped, and GMS remained to identify any GM employee discount.

That's why GMS means GM employee discount.