Nothing wrong with Gorilla Glue I use it in clear and poly form, epoxy as said by Neil is excellent I apply it both in the blank and on the brass tube using a slice of potato prior to gluing and cleaning. that I poke out using a skewer stick (the blunt end) mind you I have used most glues successfully , generously its messy but lots of tissues and patience. A well known demonstrator used to say use the glue as if someone else gave it to you and finishes as well. The only glue I wont use for brass inserts is CA since I had two stick part way in lots of mucking around spare brasses and time taken to rectify. I bought a set ofaround 1/8th inch needles used for rust impacting with a group one time they are hardened to drift the tips out of Slims and a piece of close fitting rod for the winding mechanism. The tricky part for me was handholding the top to remove the clip with the same rod, thats where the removal kit comes in handy.
The tip by Sharon is a good idea for your fail one and I have a stock of two hundred spare brasses that enable me to have lots of glue ups without opening kits and sometimes awaiting kits also I often glue up about 50 at a time.. I bought them at a bulk price. I now use the glue opened at the top not relying on the squeeze aspect my dearly beloved has been using this technique for years in her craft work its quick and less losses than squeezing out in a dish.
Instant success with your slimline receiving your thin one by the wife I agree with her choice.
Have success Bob kind regards Peter.