Camshaft card number question

Well with a starter gear of 3.09x3.91=11.96, I see no reason for running 4* advance.
If yur car goes 108 with 26s, that will be ~5500, which is well past the power peak of that factory 340 cam. Split overlap on that cam comes at around 108*, so I would be trying that, to straight up at 110; to get the Rs to perk up at 5500.
But if you had a C-body, lol, then ok I can see 106

But I'm just guessing you can hit 108@5500.
If you only hit 104, then your Rs are looking like 5300, so then the ICL could be 108 to 106
But if you only hit 100, then yur Rs are looking like 5100, and so 106 should be fine.
Tough call. A lot depends on your power to weight ratio.