Rear gear ratios

[missallpc]

I have a 1957 3100 SB/SS with a 235 and a 3 speed. I finally got the truck well enough to drive it around the neighborhood. When I'm running at about 40 mph the engine sounds like it's ready to come unglued. Can some one tell me what rear gear ratios are available for this truck and are there any problems associated with this.

thanks ....Paul