Thank you everyone for your comments and good wishes. With large manufacturing quantities involved it is quite a risk to undertake, so its encouraging the nobody has said don't waste your time. I'm pretty certain that the market could do with some kits along the lines I've described and I'll keep you all posted with progress as it happens.
A great leap forward today by the way, concerning the FP nibs. As I've said, I don't want to supply the kits with Bocks as standard as it will make the kits too expensive, and for various reasons I don't like the nibs that are supplied by either of the two manufacturers I'm currently talking to. For some reason, nibs are one of the last things that suppliers think about, whereas it won't surprise you to know that I believe it should be amonst the first. But I have now found a source of nibs from another specialist manufacturer which I do like, so I'll be able to get the kits made in one place and the nibs in another, which as far as I'm concerned is a huge hurdle overcome.