X200 P8600 MB Upgrade

[piwhy]

Hello,

I have a X200 P8600 Thinkpad for two years now with 4Gb, 500Gb/7200tr and i'm thinking to upgrade it.
I saw that the new X201 has the same HMM than the X200 and obviously the same casing.
Does the motherboard has also exactly the same design between both ?
I saw in the HMM that the only difference is a screw between x200 and x201
I saw some interrogation about the possibility to upgrade the X200 with a X201 i7 motherboard but any thread if it's really possible ?

Does someone has ever success this upgrade ?

Thank you.
PY