I have gone down the Solid glass spigot road and it is amazing how much flex there is in the Glass , when you are casting it looks like an elbow in the rod, I tried some steel golf club shaft on a bait rod and that is just as bad, I have made up a spigot from a bit of broken Carbon rod , this was much better but unless the tapers are spot on it will work loose with casting, it took a lot of building up with the carbon spray even then it wasn't great , if this is an expensive rod then bite the bullet, it's one repair I don't like doing, at least hardys will make a proper job easgach 1