Here's another way to look at it: think of the trade as currency between LVS and USD. Then an exchange rate of 1.5 LVSUSD is means an exchange rate of 1/1.5 USDLVS which is .6667. So if you break down the trades:
1) Long USDLVS at 1/55 =.018182
Cover USDLVS at 1/1.5 =.666667
=648480 pips
2) Long LVSUSD at 1.5000
cover LVSUSD at 150.0000
=1495000 pips
Okay, you still have to convert into bang for buck, but you see my point, a short can be converted into a long.