I'll try to show some setups I've used with my horizontal mill here. Can't get to some of the things I need right now -- blizzarding out. But I would strongly suggest anyone interested get David Gingery's book on building a horizontal mill from scratch.
The process of building the mill actually uses the mill to perform many operations, as well as building accessories to make it more useful. It therefore shows in very practical fashion ways of working with it nd ways of thinking to make it more versatile than just running the standard slotting and surfacing cutters. Even if you already own a horizontal mill, rather than wanting to build one, there are many things you can add to your mill using ideas in the book and the same -- or possibly different construction methods