The eyepoint can be changed. It takes a bit of XDP editing but hey - what doesn't require fiddling in this game?
In the <Views> section there are the different view directions. Find the line that looks like
<View Event="HeadStop"/>
and change it to
<View Event="HeadStop" X="0" Y="0" Z="0.1"/>
and lo and behold, your seat has moved. I don't remember which direction that one changes it but 0.1 means a 10 cm change, CFS3 is metric in that regard. The catch is that it won't take effect immediately, only after you've looked into some other direction and returned to the forward view. And this is with the "snap view", no idea if it works with the smooth panning or TrackID.