Ordering of Membership Plans

I am having a problem with the ordering of membership plans. When I create a new membership, I select the order that I want it to appear using the display order drop selection. When I look at the list on an active website, It has some items out of order. They are not following the order I have established.

My application will call for numerous personalized membership plans.
Is it possible to not have a drop down selector for the order but rather, be able to key in a custom value?