Is this a conversion where you replaced the socket in the headlight assembly with a socket that will accept the H4 bulb?
I did this in a 1939 Olds and kept the original reflectors and lens. Like you said, the light goes everywhere except down the road. I think it is because the bulb is not positioned exactly where it needs to be for the lenses to focus the light correctly down the road. The bulb might need to be slightly more forward or backward in position relative to the lense.
I think the best bet is to replace the whole headlight assembly with a complete new assembly - the light should be focused with the new reflector, bulb, and lense.
I haven't replaced mine. The headlights light up the road fairly well on hi-beam without blinding oncoming traffic. But low beams are useless except for allowing oncoming traffic to see me.