Marc,
like we talked about yesterday, consider those parts are most likely around 30 years old and its no wonder the metal fatigue sets in. You are doing your engine a big favor by swapping those old worn out screws for the swivel foot type. They were good enough for a Porsche 911/12 they will work fine in your car and the tops of your valves will thank you!
Now before I get a ton of "they don't work & stock is best!" hate mail, notice I said "Elephant foot" and not "Captive ball". Under no circumstances use the captive ball adjusters, they suck! They have a habit of launching the ball out and its small enough to find its way down a push rod tube. Also in some applications you have to grind the bottom of the rocker arm for clearance and this just weakens it.
