Change headlight bulb

H4/9003 design is, iirc, the first practical dual-beam bulb design. The high beam filament is oriented to maximize the performsnce of the highbeam, while the lowbeam filament is placed higher, and set base-ward and offset from the highbeam filament to shift the hotspot of the lowbeam lower. The metal cup under the lowbeam shield shadows approximately 40-45% of the reflector bowl from the light of the lowbeam filament, resulting in a significant reduction in light being reflected above/around the shifted hotspot.

It's actually quite a feat of engineering. It has signifocant tradeoffs, but it also represents the first breakthrough in a practical, easily manufacturable combination of bulb and lamp design that allowed us to reduce the number of lamps on the front of vehicles, and eventually their size and shape as well, significsntly, which freed up space for other components, saves weight, reduces cost of manufacture and also allowed for massive changes in the style of vehicles, which also effects things like aerodynamics and its downstream effects on fuel efficiency. It's no small feat for such a small thing to have so many downstream positive effects my dude.

 

The clip. Not the bulb is grade 9 engineering

 

a) we don't know what the OP has, lots of assumption that it is a H4 found in Gen 1.5 through 2nd. Might have a early first or a 3rd gen
b) assuming stock housings and not some aftermarket oddity or retrofit


I don't think the clip is terrible, it's the blind access and lack of description pictures in the manual that make it a PITA

 

The biggest problem with the clip(s) is that they can fall out. This usually happens at the absolute worst possible time too. Like when I was 1,300 miles from home at a hotel on a 20 degree evening and I went out to change a passenger side bulb in my 2014 Tacoma - which I had done many times. Yea, that wasn't fun.

I keep this pic on my phone just in case I ever need it now even though I no longer own the Tacoma. BTW, A little dab of RTV where the clip rotates in the housing will keep it from ever falling out again.