Rocker Arm upgrade guidance needed

[Che70velle]

Lance, I've used the vortech head on a couple of engines, and they are 3/8" studs. As far as rocker upgrades, it's a great idea to go to the 1.6's, but I'm not gonna dare recommend one over the other, because I don't know what fits the center mount valve covers. I like the ultra pro mags, simply for the weight out over the spring. I welded tabs on my heads to utilize perimeter bolt valve covers, because I went with Crower shaft mount rockers. These were race engines, for a steel headed circle track class. Again, I'm no help...