1) That's not std, but would strengthen the front.
If it goes all the way forward to the flat nose then take it out as the flat front is designed to fold backwards when you stuff the bow into a wave.
It looks really bad at the time, but springs back, Fixing it solid would soon break something.
2) The tubes just rest up against the flat front.
3) That sounds right as well.
Plenty of F4 images in one of my galleries.
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