Probably about time-rocker adjustment

I'm almost embarrassed to say but I've had my car for about 5 years and I have never felt the need to adjust the rockers. It has adjustable rockers for some reason....Not sure if it has a solid lifter setup. The rockers look to be from maybe a 273 with adjustable rockers. The car runs good but it seems to be noisier while driving it and maybe even a little down on power. I have done valve cover gaskets in the past but never felt the need to really inspect and look things over. I like to drive my car whenever possible. I have a small oil leak coming from the pressure gauge setup on the block so I have that to fix and I figured I would remove at least the valve covers and take a look. Spinning pushrods are evidence of adjustment needed . What else should I be looking out for? Engine is a 70-340