Here are a couple photos I took the other day after assembling them. They are OEM 10mm in size, threads are 10mmx1.5. The balljoints are high strength alloy, the connecting rods are carbon steel, stud nuts are serrated flanged 10.9 grade steel. Set up has left/right hand threads with jam nuts for ease of adjustment, and parts are zinc plated. Balljoints are sealed and greased.
I installed them on my car today (stock ride height), along with a set of GMPD swaybars (FYI, the GMPD front bar is hollow, the rear bar has a 2 position adjustment). Comparing them to the OEM links showed me that my adjustable links have at least the same amount of articulation of the OEM links. The OEM link's shaft is about 8mm diameter, my link's connector rod is about 9mm, the rod's threads are 10mmx1.5. The front links appear to be adjusted short enough for a lowered car (not a slammed car, though). My rear links at their shortest are a tad longer than the OEM rear links, but upon installing them the rear bar appeared to be level with the lower control arms. As a comparison, the Corvette links are 3.5" center to center, my links at their shortest are just under 4". I installed them in the same location as the OEM links, meaning balljoints are facing opposite direction in the front. I am going to see if mounting the front links with the joints facing the same direction has an effect on their performance. As a bonus, the OEM plastic clamps holding the wire to the OEM endlink fit on the connector rod of my link, so you shouldn't need a zip tie.
The rear bar on my car demonstrated a significant amount of preload when using the OEM links, which were both the same size. The front bar didn't appear to have the same amount of preload with the OEM links. This was the case with both OEM and GMPD bars.
Installation was not difficult. A 15mm wrench and socket and a 5mm allen wrench removed the OEM links. The nut on my link is 15mm, and there is a hex on the inside of the stud to fit a 14mm wrench to tighten the nut. The jam nuts are 17mm, and the hex on the connecting rod is 12mm. The flat surface on the end of the balljoint is 17mm, and I found it was useful when adjusting the links. GM torque spec on the nut is 37 lb ft (FYI, the GM torque spec on the swaybar mounting bracket is 44 lb ft).
The links may be shortened further, but that would probably require the female balljoint being cut down a bit, as well as the connecting rod. Just a visual comparison, from photos it looks like that's what Powergrid did on their balljoints for the rear of the V, but I may be incorrect. The photos I saw appeared like they cut off the section of the balljoint that has the 17mm flat section.
I need someone with a set of H&R or Eibach springs to install them to see how they will work on a lowered V.
I already have 2 sets out there for testing and evaluation. I think the GMPD bars on my car will put them to the test.
Once I am satisfied they work properly and can handle the heavier GMPD bars, I'll make them available to the community. I'll sign up as a vendor at that time.