Take the bus; it's a bit of a hike to TBIT.

You will have to re-clear security; it's a landside connection. You will exit the secure area, travel over to the TBIT, then go through TSA again. No additional screening beyond that.

To me, 1:50 seems okay. I've taken a connection not much longer than that, exited security, hopped a shuttle over to the Parking Spot, had In-N-Out Burger, then shuttled back to the airport, re-cleared security, and flown out (this was before the days of PreCheck, too).