abga,
I have already followed the advices in the post you mention, and have cloned the git but the rpi-4.9.y branch pulled out the 4.9.80 ( according to Makefile : VERSION = 4 PATCHLEVEL = 9 SUBLEVEL = 80 ) and mine ( sarpi ) is 4.9.5
I think that I will fall in the same problem.
That's why I was asking for the linux source used to build the sarpi kernel.
In case I won't find it I will try to build a new one, or even try to download one following the instruction on site but it don't seems to be so easy