Secondary throttle blade testing

[Kahuna]

Guys, I recently posted about mileage and about the need for a different rear bearing for my "generator" fan mount.
This question is in regards to being able to check the secondary throttle openings on the 2 4bbl carbs and how to do it?
I'm thinking of buying one of those "GoPro" cameras and afixing it to the firewall so that I can see if the secondarys are actually opening and how far?
Do any of you have, use these cameras? If so, what all is involved in their use?
I've seen where their use is on windshields to video a trip, etc.
My friend Lou has one and sent a video that he made. Just wondered what others have done.
Any info is appreciated
Thanks
Jim