Marking a task as complete in the parking lot

If I mark a task complete in the parking lot you should ask me what day it was completed.  Then promote it to the week plan&do module. I don't want completed tasks in my parking lot. I want them in a history on the day that I completed them. When I clean up my parking lot periodically I find tasks that I completed weeks ago and I want to "give myself credit" for those but I don't want them recorded today, I want them stricken through and archived on the calendar day I did them (which I could provide.  You would put today's date as default and I could edit it before committing to a historical date. The task would then leave the parking lot and go to the date I said (today or history) and persist as a completed item.