How do I update my MacBook Pro to the latest version of BootCamp? Running Windows 8.1 on my 2013 Macbook Pro that runs OS X 10.10.5. 

Want to update the version of BootCamp (and related drivers) that it is running - I don't think it has updated since I partioned and installed Windows 3-6 months ago and I know there have been updates.


I was notified within Windows via Windows Update of new BootCamp and tried the update via Windows update but it failed
Running Apple Software Update within Windows doesn't give me anything BootCamp related to download &amp; install - this Apple Support Article  says that it will be available via this channel but it's not?
The options from within Yosemite + BootCamp all seem to entail a re-partition and reinstall of my entire Windows partition (naturally not first prize) 
Download of drivers onto a USB stick from Apple website but this also seems to involve a re-partition.


My end goal is to perform the free upgrade to Windows 10 without reinstalling but I am trying to get BootCamp in order from the beginning.

Related question: how can I tell precisely which version of BootCamp I am actually running. From within Windows I can right click on About Boot Camp and it says 5.1 but this is not specific enough.
Open BootCamp Assistant and open the about window. You should be similar to Version 5.1.4 (500) if you are on 10.10.5

BootCamp gets updated when you update OS X so it's really not dependent upon any version of Windows whatsoever so you would be up date on BootCamp even if you deleted your windows partition and started over.