problems Water pump and thermostat Help identifying plastic part found in thermostat housing

I have a 1995 Toyota Tacoma 2wd Auto 2.4L. I was installing a new water pump, hoses, and thermostat today and ran into a couple of problems. I go the new water pump on and was trying to follow the FSM directions for torque specs on the 10 water pump bolts. The FSM advises torqe for "14 mm head bolt : 24.5 N-m (250 kgf-cm, 18 ft-lbf)" and "12 mm head bolt : 8.9 N-m (90 kgf-cm, 78 in.-lbf). The problem is my water pump has 2 long bolts with 12mm heads and 8 short bolts with 10mm heads. So, I'm not really sure what torque to use on these bolts and I really don't want to deal with a leaky gasket and have to do this all over again. Any advise here would be greatly appreciated.

The second problem I ran into was discovering a small plastic part sitting in the bottom of my thermostat housing. Not sure what that could be and hoping that someone can advise where that might belong? It was just sitting in the bottom of the bowl just like pictured when I took the housing off.

 

Looks like a radiator drain cock that was broken or dislodged.

 

Well, for a 2.4 camry those 10mm bolts on its water pump is 80in-lbf

see at 6:30....

Water Pump Replacement 02-11 Toyota Camry 2.4L (youtube.com)