It's been a while since I had to drive my '78 in the dark. The stock sealed beam headlights had me squinting the whole way to work. As soon as I got there, I ordered some 9" glass headlight housings with replaceable H4 55/60 watt bulbs. After installation and alignment, they're only a little better.
I've upgraded a '95 Tacoma similarly and bought 80/100 watt bulbs for it. It was a great improvement. Can the 280 wiring handle 80/100 watt H4 bulbs?