Treeman,
I'll set either with a throw or bigshot to the mid canopy around 65' and then do pitches to the high forks which are fairly open on the main leader all the way up. As best that I can tell I have agood TIP about 10' from the very tips of the upper canopy so I'll attach the tape to a painter's extension pole from there. I'm going to stick to the center leader and not do any lateral movement and won't get too much into any weak forks for exactly the reason you stated. This tree does have some broken limbs from heavy mast in the outer canopy, mostly out away from the center but up in the upper third- if that makes sense; however it does not have many, if any that I recall, included forks surprisingly. I think this is one of the reasons this tree is so big and old. It's a real genetic marvel. An Arnold Schwarzenegger of the Carya genus! Eets really pumped up!
Sure I'll take some photos and I'll have my groundie take some from below as well to get that perspective of how small we are-really.
Treeman I hope this finds you well and happy, say hello to Patty for me>
Peace,
Longfellow