I used a Pacer clip, as some others here have. I’ve always been happy with the results. (Although it’s in pieces all over the garage now as I try to get it all rebuilt before spring.) There wasn’t much to choose from 15-16 years ago when I put it in. Never cared for the Pinto/Mustang II kits, as they seem too narrow for the AD chassis. But I would use this if I were going to do it now…
http://www.chassisengineeringinc.com/page9.html The bolt in design, available engine mounts, 2” adjustment of ride height, and they fixed the width problem. Looks like a well thought out kit to me.
(ps…This is not an ad for that company, just my opinion on the subject)