The title says it all. The Tindie page says
Processor : i5 or lower -> 65W , i7 -> 90W
And I imagine the Intel Core 2 Duo L9400 (2) @ 1.867GHz my X200s has fit in that i5 or lower category but I just wanted to get a thumbs up before I pull the trigger on the 65w version.
If you are interested in USB C charging mods yourself by the way he has versions for different models.
If you haven’t done this already a 65 watt adapter should be plenty. The only benefit to a 90 watt adapter is the faster charging speed, and if you remove the battery it will still run the CPU at full speed. With a 65 watt adapter it should throttle the CPU to it’s slowest speed.
The biggest down side to the 90 watt adapter is that you have to use a ~80 or greater charger because the second the laptop draws more than 65 watts it’s going to trip OCP on your charger and shut it off.