Glad to hear about the clean up; that is wise.
The valvetrain upgrade you are facing is more than fixing broken parts. You are putting in much heavier lifters and the lift rates are going to be much higher. And you have unknown rocker geometry. So there are at least 2 things that are requiring more spring pressure and valvetrain strength, and the geometry may makes it all worse.
I'll say again that the rollers being centered on the valve tips is not any indication of good geometry. The main thing you want to look for there is how wide the scrub pattern has been. Do you have a pix to share of the present scrub pattern on a valve tip?
