Ubetcha on the horizontal eyes.....I've fabricated links for both types and it lets you tune the suspensions a whole lot easier. I've made adjustable links for some 4 wheel drive applications with the vertical eyes and even a few that could be easily detached for off-road.
The thing that most folks don't realize, is that using both front and rear sway bars will dramatically improve the handling of even a 60 year old truck. Just no reason to have to use a grab-rail and tense up when approaching a corner!!!
Dave