Hi doubles partner, how are travelling so far?
I'm 3/450.
To go Overton to Pope to secure the 78 you would want to be of the mind that Pope was a player you were pretty interested in anyway. Otherwise, if you rate Overton much higher, then stick fat, or find an alternative route.
Just quick sums off the top of my head, if you rate Overton at 50/game, then keeping Overton potentially only costs you 28 points, but then you have a committed trade next round. Hard to rate Pope, given he has little short game form. You'd want to be rating 40 at least to consider the switch.
Personally, 78 isn't a high enough SGR score to pull your plans apart to get. Those 100+ scores are a different matter.
Good luck which ever way you go.