mounting door poppers on an old school sdime

I need to mount my door poppers(on an old school s-dime), but not sure where the best place to bolt them 2......i was looking at the bottom of the door where the rubber bushing is...but i noticed that it would be on a downward angle so not sure if that will work quite right.......then i was thinking above the door latch and actually mounting to the door itself...not sure if that would work either

if anyone can tell me where the best place to mount the door poppers are id appreciate it

thanks