I'd totally agree with your response to ZX9RCAM in regards to wiring, contact resistance etc. However 20A is 20A with a fuse - Size doesn't matter - whatever the men say. Maybe I mis-read what you were saying about "larger format" - I thought you were talking about a fuse size. In which case, I apologize.You're absolutely correct. Not like I spent over 40 years working on cars and trucks.
I'll let you explain how it works.