[mr48chev]

Looking at their site I have to think that the anti lock just isn't in their wheelhouse. Meaning that it is a separate system outside of the engine management systems they work with.

Antilock brakes work when you really have to lay on the brakes and keep you straight rather than let the rear of the pickup come around. I've had the rear brakes on pickups lock up and one ended in a spin out that sent me over a bank and I rolled the 70 Chev 2-1/4 times according to the guys who saw it. I locked up the rear on my 71 GMC and spun out when I Locked up the brakes to keep from hitting a Geo Metro that zipped out in front of me and that guy still doesn't know how close he came to death that night. I was doing 60 when he cut in front of me. Spun the truck 360 and the spin was so hard that it broke the alternator bracket.

Had a Mustang rag top that was doing somewhere around 140 coming down the road hit the brakes when she finally saw the stalled semi and wrecked car blocking the road in front of my driveway one night hit her brakes and while she didn't get stopped the anti lock kept that car straight rather than spinning. She still hit the tank truck and killed the guy in the passenger seat. It sounded like a car racing at Bonneville when she was coming down the road as you could hear the air break around the car a mile down the road but didn't hear the exhaust.

That simply means that if you can figure the anti lock out it will be worth the effort.
Stopping straight lets you maintain control unless you are going crazy fast.