Problems with 1961 rear differential...need advice

[par4tom]

I've looked through some of the other threads, but can't find the correct starting point.

I have a 1961 Chevy truck, that has an L48 out of a 67 Camaro Supersport. Anyway, the truck still has the SM420 tranny and the original rear differential with posi...I think it's a 4.11 ratio.

I"m looking for what I should do, either to the tranny (less preferred) or to the rear differential (More preferred).

The truck makes about 330hp with a mild RV cam, and I'd like to use the truck occasional to pull a small travel trailer, but I'm concerned about getting the gearing wrong. I've seen some guys change the rear ratios, but opinions seemed varied.

Again, I'd like to keep the tranny (I realize 1st gear is of little use) if that is possible.

Would like to have some decent pulling power, but more importantly, be able to cruise down the California freeways doing 70, without the motor being so wound up. Can somebody help me with where to start?

TC