I would go another step further and only use 2.5mg a day until you're out. I know that choppin up iddy buddy pieces of pill feels stupid and pointless but this way you would have 12 day before jumping completely. No matter how you do this its gonna involve some withdrawal pain. So that's my suggestion.
Plan A:
You could take 5mg a day for six days, and it would ween you to some degree but not much. So you'd have 6 days of "meh lemme go to bed" then a week or so of acute withdrawal anyways cuz 6 days isn't long enough to taper properly.
Plan B:
Now going my route will give you 12 days. In terms of opiate addiction, withdrawal and tapering its not much. The difference will be that you will feel like "meh lemme go to bed" for 12 days ,then a week or so of slightly less intense acute withdrawal than you would have had doing plan A. I know dragging the "meh" phase out almost seems counter-intuitive but this will give you and your poor brain a little more time to adjust to not dosing throughout the day and begin the process of changing/stopping your using rituals. So you'll have twice the time to adjust yourself to living without the meds before you are thrown into full withdrawal.
Method B should also help with what I like to call the rebound effect. As in people getting clean then going and starting the whole mess over again within only a couple days clean under their belt. You'll have a few more days to adjust to your triggers and build a support system before you even jump into hell. You should also use that extra time to load yourself up with vitamins. And take them all the days leading up. This should make everything more tolerable.
I use this method or a slight variation of it every time I have an extended run on pain meds. It's definitely much better than buckling in for a cold turkey trip.