I put some Sylvania SilverStar's on my 76, and it made a world of difference. I had already "upgraded" from the old sealed-beams to halogens, but the Silverstars really light it up. The only problem I had was that I had to modify the plug a little bit because the dust shield (for lack of a better term) didn't allow it to plug in all the way. They are quite expensive for headlights IMO, though. I think they were around $25 each at O'Reillys.
I liked the Silverstar headlights so much, I went back and replaced the turn signals with Silverstars too. I have the clear lenses with the amber bulbs. The new bulbs are blue on the end, so you can see a blue spot through the clear lense, but when they are lit up, all you see is amber......it's kinda cool IMO. They were a bit pricey too....I don't remember how much, but not cheap.....
Mike