I have a request for a Jr Statesman postable. I only have a Jr Statesman non-postable, but I do have a Jr retro and a Jr Gent postable. Can I assemble the pen with a retro or gent postable end, and then when I receive a Jr Statesman kit unscrew the tip off of the postable end and put the statesman end on? Does anyone know if they are interchangeable? I will be sending the pen out for engraving, and I would like it to be assembled during this process. I won't deliver it until the statesman part comes in.