Howdy:
I just wanted to offer a suggestion on using Recycle yard rocker arm assemblies. The may look ok on the outside and easy to clean up with solvent, but the real cleaning needs to be done on the inside of the rocker shaft and the oil holes in each each of the rocker arms. There are two holes, one at the 3 o'clock position when viewed from the front and one at about the 10 o'clock position. While you have the rocker arms off the shaft, check the bushings on each. The front one will show most wear due to lack of oil, especially at start up.
I'm running a set on my engine and I couldn't believe the gunk on the inside of the shaft. I finally used a shotgun barrel brush and lots of solvent to get it all cleaned out. The before and after difference on how long it took to get oil to the front of the rocker on cold start up was significant. Just thought you should know.
Adios, David