I hate to say this publicly, I can’t remember who I got the first set from here on FABO. Second set I got from Sam. There are a few fellas here that ran them. They have the rest of the wealth of information on these heads.
I hope those do you well. I sold them to buy my square decking setup. I really hated to let them go. I bought them from a guy in KY, and wish I would have picked up the R3 block he had, I didn't want to drive 4 hours...I just had him ship the heads, live and learn.
