Slide Wiper Seal Replacement

[tntfla]

I recently replaced the outside vertical wiper seal on one of my slides. Not a hard job. The worst part was removing the glue from the old seal.

Now my question: at the top of the seal there is a small countersunk screw that goes through the seal to hold it on the body. Actually this screw is probably mainly for the slide in bulb seal that is an integral part of the wiper seal, to keep it from sliding down and away. This screw appears to be a star head and it is short with what seems like a type of captured nut that it screws into.
It was very tricky trying to hold this nut in place in order to thread the screw into it during replacement.

Does anyone have any experience with this screw and able to reveal a trick to getting it back into the nut?

I do have one more seal to replace and some advice would be great. Thanks!