As far as sending in the ferrules, I think you would just have to send them to me with details of the build you want. I would then have one of our folks contact you to get the order placed. As far as swing weighting without tip weights and the hand picking, not something that we can do. Tolerances are pretty good these days and finding variations enough in the components to make up for 1-2 swing weight differences would be tough. Even if it was possible the number of components that would have be gone through is just not efficient for us to do because the warehouse is separated from the assembly area. Anyway, small amounts of tip weight used to dial in swing weights is common and does NOT effect the playability of an iron as long as no more than 8 – 10 grams is used, and we never need to use that much, unlike many of the OEM clubs we see. We did a test once to see how much cg is moved with tip weighting is used and 10 grams moved the cg approximately 90/1000″, or a little less than 3/32″. So the more common for us (if needed at all, depending on the build) 2 – 4 gram tip weight added would move it much less.
Hope this helps. Let me know if you decide to send in the ferrules.