It looks like you could rotate your alternator closer to the valve covers, mine is very close, getting the belt on isn't easy.
View attachment 10063
I've just noticed my stay goes behind the alternator, you've got yours in front, I think that's twisting it.
Oneball , Your alternator looks too far back along the side if the rocker cover . Also the pulleys don`t line up unless it is just the camera angle . Mine is a 1980 though .View attachment 10066
Hope this helps, this is an original ‘78 but with a belt guide. The guide protects the top hose in the event of a belt failure. The biggest problem I had was access to the PS reservoir filler and level gauge. Never had a problem with belt removable or tensioning.