VS middle nose rib flange not flush before riveting

Well, I probably should have spotted this before riveting, but after starting on the middle nose rib, I now notice that the very tip of the nose flange isn't sitting flush prior to riveting. (In the photo, I had just popped in the rivet prior to taking the photo).

I'm using a tungsten long rectangle bucking bar and I can't quite get my fingers on the flange to push it up.

Any tips on getting the flanges to sit flush before riveting? Would the shop head push the flange flat? Or would it expand between the flange and the skin?

Also, just started riveting the skin and if you see any issues with the other rivets, please let me know! Here to learn!

Much appreciated!

Cheers,
Dave

Below are links to two YouTube videos where the builders discuss this very topic and the use of a rubber or plastic donut on the bucking bar to hold the flange tight when riveting commences -

Here is PlaneLady's - you can jump to 11:00: https://www.youtube.com/watch?v=xGHZ...9_N9J&index=37

Austin Manke's @ 16:50: https://www.youtube.com/watch?v=cvwDYFGeK6s&t=696s

Amazing, thank you!