Just FYI, I saw H4 conversion housings on the shelf at Auto Zone today.

It appears that these are now sold off the rack. The set that would fit our cars was $40 - WITHOUT bulbs. Not that great of a deal, really, but pretty easy to buy. The lenses were glass and they had a similar design to the diamond backs.

They had conversion housings for all four of the old style sealed beam headlights (2 round, 4 round, 2 rectangle, and 4 rectangle). I just thought it was interesting that this particular mod has gone so mainstream. I did it to my 72 Pontiac back in 1984. Originally, a firend of mine gave me the high/low beam housings (the outer lights on a 4 round system) from his mom's wrecked BMW. It was a good mod then and still is now!