Yes, from what I read I would likely need to get the +2 if I go taller.
Reasoning:
Currently, for my stock passenger seat, I have 1.5" spacers so my dog can see over the dash and the top of the seat rubs the mesh canopy when folding the seats forward. This caused me to be mindful of height constraints, which I previously never considered.
For that reason, I don't expect +4 to be a viable option for me (when also considering that the 03-06 bracket is listed as a height increase of 1/2") because I don't want major interference issues hindering me from folding/reclining the seats.