Sorry, I realized I wasn't clear in my last post. I meant to say try disconnecting the red wires from the switch and tape over the ends and leave them off before trying another trip with the fuse installed, to completely eliminate the switch as a possible short. Then all that remains is the red wire back to the fuse box.
You're correct that you can save the fuse by pulling it before travel, but what I'm saying may happen is if the short remains after you stop, the fuse will blow when you plug it in.
One more thought: Is there anything else on that same fuse that could have an issue or is only the slide non-functional with it pulled?
And another thought: Since the fuse is at the bottom of the box, is there any chance a bare ground (wire or sheet metal) is near the fuse or terminal where the red wire connects at the fuse box?