Aluminum trim question

I have purchased my trim for the roof. It is an aluminum insert trim.
My questions are these:
1) It did not come with the holes pre-drilled so how far apart should I drill the holes.
2) Would butyl tape be a good sealant to put under the trim?
3) How easy is it to bend around curves? It seems pretty bendy but has anyone had problems with the outside lip bending on a curve?
Thanks

My questions are these:
1) It did not come with the holes pre-drilled so how far apart should I drill the holes.
2) Would butyl tape be a good sealant to put under the trim?
3) How easy is it to bend around curves? It seems pretty bendy but has anyone had problems with the outside lip bending on a curve?
Thanks
