FYI - I've done a similar thing, but DON'T bash them out - if you take to the lenses with plenty of heat (but not too much or the plastic melts!) you can remove the clear front lenses - they are attached to the rest of the mounting with a rubbery adhesive.

The glue softens - take your time, and go around the edge bit by bit - you can then remove the outer lenses and then the amber lens inserts can be unscrewed (they're attached with two screws). Change the bulb to an amber type and then apply more heat to re-soften the glue and put the lenses back on. The glue seals up well, but if there are any areas that don't - use a bit of silicon.

An alternative, which is what I did is to swap the indicator/park wires around and use an amber bulb in the outer mounting (original park light). Actually, I couldn't find an amber bulb with a blade type base in 21W, but obtained a clear one and used a amber 'bulb condom' on it. I now have 21W (you could probably even go brighter) park/mini headlamps, and for inner city driving, don't bother popping the headlights up.

I've got photos etc of the install, and will get around to putting together a writeup one day. You can sort of see the lights here http://www.mx5club.org.nz/members/fox/plates/ but not very well. (6/01)