'78 W900A No Power To Dash

I have a '78 W900A that for some reason has no power to the dash accessories or lights. All that is working is the ignition switch. Everything was working fine and then when I went to start it this morning nothing. This same thing happened a few months ago and when I replaced the alternator (which I was doing anyway) it all started working again so didn't look into it any further. I've checked out & cleaned battery cables, fuse box and grounds. Everything I can find here and elsewhere online is for a newer truck. Anyone have any ideas?

 

Found it, ended up being a ground even after I'd checked them twice...Put a new ground and it fixed the issue.