Magnum/Chevy rocker studs?

Comp Cams 4542-16 studs is what I'm using (on my EQ magnum heads) which fit the magnum heads no mods needed, using Comp Cams guide plates for the magnum, all with the older red Comp Cams 1.6 alum. roller rockers for a SB Chevy. From all I researched these were the studs needed. The longer ones you mention may be an option for higher lifts, installed spring heights. My lift is only a little over .500" lift, cant recall at what spring height either are good for.