Since I have my license I can't answer your main questions. I just wanted to point out that if your handgun is a semiauto, just be aware that you will have to not only have the gun empty when entering a motor vehicle, you will have to remove every round from your magazines for the gun to be "unloaded" in a legal sense. Speedloaders for revolvers also have to be empty for a revolver to be considered legally unloaded.
The law doesn't say you can't open carry in a vehicle without a CHL, it says you can't carry a loaded handgun in a motor vehicle without a CHL whether that handgun be open or concealed carried.It states that you cannot open carry a firearm inside a vehicle without a CCW.
Here are some resources for getting familiar with Ohio gun laws:
Ohio Attorney General's Manual on Concealed Carry:
Ken Hanson's book:
Sean Culley's book:
Ohio Revised Code: