I FIXED IT!!!
turns out i had saved it wrong, the correction is in the “position” expression:
s=thisComp.layer(“TEXT 1”);
w=s.sourceRectAtTime().width/2;
h=s.sourceRectAtTime().height/2;
l=s.sourceRectAtTime().left;
t=s.sourceRectAtTime().top;
[w+l,h+t]
the width and height needed halving to prevent the overshooting.