how to partially merge iPhoto library with iCloud photo app

[matc]

Hi guys,

I signed up for a 200GB iCloud plan and my current iPhoto library is way bigger.
Therefore I'd like to merge only the last 2 years of my current iPhoto library with my iCloud library and put the rest on an external HD as an archive.

Any idea how I could do this? Would the photo app be smart enough to discover duplicates when partially merging my current physical iPhoto library with my iCloud library...?

 

[Weaselboy]

The only way I can think to do that would be to manually export the last two years out of iPhoto then import them into the existing library in Photos.