MBE 4000 Coolant Change Question

I am a farmer, not a trucker, and we are new to running a semi, so bear with what are fairly straight forward questions.

I have a 2007 Columbia with the MBE 4000 engine. I checked the coolant with test strips and there is no SCA left, so I am going to change the coolant. The manual says to drain the radiator and refill, no mention of a block drain or anything. Here are my questions.

1) The manual mentions opening the water regulating valve. Where is this located?

2) Is the only drain point the radiator? No block drain? Any other drain?

3) Does this truck have a coolant filter? If yes, where is it located?

4) I don't have access to the truck right now, so I can't just go pop the hood and look. Is there a cap on the top of the radiator, or do you refill through surge tank?

I appreciate your patience and help for a newbie.