disconnecting the negative technically works better since the theory is that electricity actually flows from negative to positive. Although I'm sure you've heard that before if you're an engineer. That's what I've done for years with all auto electrical (i'm an installer). If it's hard to get to and this is something you plan to do regularly I would pretty much do what you were thinking for the positive, but on the ground side. only have to take it off once and put a quick disconnect on it with a larger gauge section from that back to the battery. might even do the big three while you're at it.
part of the reason for doing ground instead of positive is that some component will still hold a charge for a while after battery is unhooked, taking away the ground not makes it impossible for anything to short out.
2010 Volvo C70
2011 Harley FLHTK
Midwest Crew #22