Manual Steering ratio, recommendations? 16 or 24 to 1?

If you have power steering now, just remove the belt and drive it. Ratio is 16:1. This will give you a real indication about the effort and feel. I drove my 68 SB 68 cuda like that for a few years.

Fast forward a bit and I replaced it with a 16:1 factory manual box and during the first drive there was no perceptible change in the effort. This is with 215/60x15 radicals. Yeah it's a bit difficult parking at low speeds but like the t-shirt says "Real men drive Mopars"

If you are drag racing, the 24:1 is the most desirable because it's not as touchy in a straight line. If you are autocrossing, you do not want 16:1 manual. It's a little tough to keep up.

My 64 Valiant has 24:1 manual and it is slooow but effortless with 195/70 tires.

I have a new 20:1 worm and sector that was sold by Direct Connection way back when. You might luck out and find a NOS set.

The story I got about the 20:1 is Chrysler developed it for NASCAR. 16:1 was too fast, 24:1 was too slow and 20:1 must have been just right. It was later offered by DC because it was in the system with a part number.

If you are starting from nothing, I'd go for 20:1.