Greetings everyone. I have the opportunity to shoot an annular eclipse later this month. I'm looking for advice on how to best shoot this rare event. I am thinking about renting a 1.4 or even 2 extender for this. Basically, I need to know if the gear I have below will be adequate to get a decent capture. Using advanced theoretical mathematics, I figure I can get a reach of 448 mm using the 1.4 extender and 640 mm with the 2.0 extender.

Gear:
7D
70-200 IS
tripod
B+W ND110 (10 stop filter)
various LEE GNDs

Much obliged for your expertise! Erno (image taken from Google Images)
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