On the Magnepan 1.7i, it does require an irreversible mod. You have to cut the yellow wire going to the fuse block, and then resolder it to the post.
The yellow wire is connected to the fuse block via quick disconnect terminal, what you need is use a pliers to pull it out from the fuse block.
Then install a male connector ( you might need to enlarge the hole to fit into the binding post ) on the binding post that was soldered with black wire and push in the yellow wire.
That's it !!! The fuse is bypassed now, It's that simple.