Originally Posted by wpoll

Used the nifty mod on the AE reflector to create little slots to allow the BA9 bulb bayonet pins to pass through the central hole.

This video shows the mod. It's not E53 but there are almost the same (reflector and bulb are identical).



I used a dremel with a small drill bit to create the bayonet clearance notches but a small wire wrapped around a soldering iron would work well too.