Honda S2000 AP1-to-AP2 ("04") Front End Conversion

Decide up front whether you are converting the bumper, the headlights, or both, since the panels are cross-compatible across model years. For the headlights, choose one of two paths before ordering. Buying the AP2 HID ballasts (around $500) lets every bulb seat directly into the new housing with no cutting, giving an essentially plug-and-play result. Reusing your original ballasts saves that money but forces you to modify the new housings and build mounting brackets, as covered in the following steps. Order the AP2 bumper cover, grille, and front tow hook cover together; the grille and bumper ship without the clips that join them, so plan to transfer the originals.

Detach the factory front bumper cover and both headlight assemblies to expose the mounting points and the front support beam. Follow a standard S2000 bumper-and-headlight removal procedure for fastener locations and the order of disassembly. Keep all original hardware and the grille clips, because several pieces are reused later.

This step applies only if you are reusing the original HID ballasts. The wiring opening on the underside of the AP2 housing is smaller than on the AP1 housing, so the old ballast leads will not pass through as-is. Score and open up that lower opening with a razor blade, then clean it up and thin the surrounding wall with a rotary tool until the original ballast wiring can be worked through. Take your time feeding the connector through the enlarged slot.

The mounting-bolt pattern on the original ballast does not line up with the AP2 housing, so it cannot bolt on directly. Cut short pieces of aluminum or thin metal strip and shape them into straps that clamp the ballast securely to the new housing. The result is not cosmetic, but it holds the ballast firmly. If you bought the AP2 ballasts instead, skip this step entirely.

Wrap the seam where the ballast meets the housing with electrical tape to block water and moisture from entering the assembly. Because a reused ballast sits in a fabricated position, check that it does not contact or rub against the chassis once the light is on the car; reposition or pad it as needed to keep it clear of the frame.

Set the AP2 headlights into place; they share the factory dimensions, so they seat and line up cleanly against the fenders and bumper. The units tend to shift as you drive the bolts, so have a second person steady each light while you fasten it, then fine-tune the position before final tightening. Owners report the beams line up correctly with no aiming trouble; note that US-market housings use manual adjusters, which right-hand-drive builders set once and leave.

Where the AP2 bumper bears against the upper corners of the front support beam, it will leave visible dimples in the finished panel unless those corners are relieved. Grind or shave both of them back, or, as an alternative, drive them inward with a center punch and hammer (a hammer and iron rod works too). Some builders remove the support beam entirely to save weight, since it runs roughly 9 to 12 pounds, though that sacrifices the front structure it provides.

Move the eight metal grille clips from your old setup (four along the top, four along the bottom) onto the new bumper, since the AP2 bumper and grille arrive without them. Seat the grille and tow hook cover, then hang the painted AP2 bumper cover. Have the cover painted at a reputable shop beforehand for a clean color match to the body.

The AP2 bumper is slightly wider along the bottom, so the central fasteners (about six) line up while the outer ones (roughly four to six) sit too far out to reach the undertray; with AP1 splash shields you may only catch about four of the ten lower bolts. Bridge the gap by cutting small plastic or aluminum tabs (around 2 by 4 inches) with two drilled holes each, fastening one hole to the bumper and the other to the undertray, or simply zip-tie the outer edge. Leaving the lower edge loose lets it vibrate and can spider-crack the paint over time, so hold it down one way or the other. For a fully factory fit, the AP2 splash shield retro kit (about $160-175) is optional.