Guys like FerretWYO are always a big help. I think grinding the base off of the quills works pretty well. But if I can strip the base off it gives me a thin layer of the membrane that holds the quills and it is kind of curved of domed. So it fits really nicely onto the membrane you are splicing onto. Just what I have found to work pretty well. I am sure if you do a search for "splicing" you will get lots of info.
Well I have to get to making some more. I have some shafts that are already for fletching, they just need some of these spliced fletchings now!