Took eons to find a clean HX manual. Picked up off C/L for $2700, intact with 122K.
Hardware store air dam/side skirts, Michelin Defender LRR tires, Valvoline SynPower oil, B&M short throw shifter, Energy Suspension poly shifter bushings, eBay lowering springs, eBay front strut brace, Sparco R100 seats, AppLink head unit, a bunch of OBD gizmos ...
Aero! Nose, tail, belly ... instrumentation, possibly in-board mirrors, maybe something to bump HP (not sure exactly what).