Swapping fuse box

Hello, so I had a question regarding the old fuse box. The one on my 1978 xs is trashed and Im doing a scrambler build, so I got a new one. I got one that is meant to come off the battery and have the whole fuse panel hot all the time, but didn't think about the fact that it needs to be keyed at the time.
So my question is, can I not just have the hot wire from the regulator go to the battery like normal, fuse it seperately, then have the brown wire coming back from the key switch power the fuse panel, so that it only has power to the accessories when the key is on?
Included a pic of the new fusebox