Honestly, the only one I have any experience with is the Alterkation. We used those in a restomod deal and they seem to be fine. Car drove great with that and a 4 bar in the rear. I'm sure others have had experience with other units.

There are places that do suspension kits or you can probably source it from NAPA or somewhere. I try to avoid Chinese stuff, but that's hard to do these days. If I were replacing stock stuff, I would probably go on and convert it to '73 and up parts.

If I were building a new car, I would not use a D60 if it were free, unless it were a Stocker and had to be that or a 8.75. Too many negatives. But, ignoring my preference for the 9" - I've seen a lot of cars built where a used rear, that someone pick up cheap, was used and the car was built to the rear, rather than the other way around. They usually end up being a mess - built in a driveway somewhere and not close to being right, brackets are junk, driveshafts run crooked, wheel spacers needed, wheels not in the same place one side to the other or they have to use some queer wheel offset, 4 link is a mess and no way to get the bars in right, etc.

I wouldn't consider it without close inspection and being satisfied that it exactly fits my needs - who built it and was it done correctly; is it straight, square and not bent; where is the pinion offset; how wide is it; what is the C-C of the 4 link brackets; are the brackets 20 years old with an obsolete geometry; etc.? If the car has to be substantially compromised to use it, it's not worth it if it's free.