Drain cooling system

I have a 98 SL2, 106,000 miles. When I attempt to drain the radiator, the plastic draincock will turn counter-clockwise 1/8 turn and stops. It feels as if it would break if I continue to force it. Do I pull the draincock from the radiator at this point to drain or continue to turn counter-clockwise until coolant flows? Also, is there a plug(s) in the cylinder block that can be removed to drain it?

The drain plug for the block is located in the therostat housing. You can drain the block by removing the plug on the bottom of the housing. As for the radiator drain look you will see the slot that the plug slids down. I think you need to push in a little on the plug to unlock it the pull out as you turn the plug.

not sure if its the same but on my 93 you turn the plug on the radiator, thats it. and the drain plug/bolt is under the block. you'll need to remove the drain plug if you want to completly flush the coolant.