... and the MSD box really does only pull 1 amp per 1000 RPM. Here's a thread on the MSD forum where the MSD tech talks about it:
https://www.msdignition.com/forum/showthread.php?t=4242
... and the box itself has a 15 amp fuse soldered to the board itself -- so there's no reason to add a fuse to your MSD box load because they've already done it for you.