I have a few Indian eyedroppers that I have yet to use. I would like to ink one up this weekend, but I'm not sure how to clean/rinse/flush an eyedropper without disassembling the feed and nib from the section. With a convertor or sac, it's quite easy to rinse the pen, but how do you rinse/flush an eyedropper without removing the feed and nib? Thanks in advance.