THe guide recommends 150 feet or 150 yards?
If this is a trip you spent a good amount of money on AND been looking forward for a while, spend a little extra coin on GSP backing.You can fit a whole lot more on your reel. Also, a .25" on the outside of the spool means a lot more line than a .25" on the inside of the spool. I think you should be fine to get 150 yeards without cutting the line