My tappets "look" good - no marks on the sides of the rollers, needle bearings feel good and only very slight scuffing on the sides of the exhaust tappet bodies. I just don't know if they will all pump up. I hate throwing $200+ at it as a guess, but that is probably what I will end up doing.
I found a set of adjustable CroMo "Time Saver" pushrods I like for a good price that I will order when I am ready.
As far as gear lash is concerned, my noise seems to have appeared "suddenly", but it may be that I just didn't notice it until it became excessive. It seems to me that gear lash noise either be there all the time or gradually increase over time. I have a set of .108 pins on order so I can check it, but this is a new noise. Looking at all the parts, wear is not evident. All the bearing surfaces look good - smooth, no groves or pitting.
Before I start ordering parts, I've still got to pull the heads and jugs off to get a look, but I'm getting close.
Thanks again for your input Dave, it is also very well informed and I sincerely appreciate it.