What I think I know:
The early boxes are 3.09-1.92-1.40-100; I got my gearset from Passon. He said it was from a 65-273. I also needed to purchase a long shaft from him for the GV, which I put behind it.
The 3.09-1.67-1.00-.73od can handle a street 360 in first and second ok, but I blew two od gears up and one input...... on the street with BFG 295/50-15s and no traction aids. The dinky od gear has either 21 or 18 teeth on it, so is very weak( diminutive, for sure,lol). Yeah that's 21 OR 18, depends on the model you get, and you cannot swap parts between either box! So I had to buy a third box! And another spare,#4. I now have a rack full of 833 junk,er, used-parts,lol.
I've been abusing that early box for over 10 years with over 400hp, and split-shifting the GVOD without a clutch, so IMO she's a keeper.
And you are right about the 1-2 shift! It is 54% so when you rev it to 2800, my chosen "normal" shift rpm, the Rs fall to 54% or 1512, so your engine better have some balls down there, most hi-perf V8s don't. And in 1.67 ratio the non-Hi-Compression engine takes forever to accelerate up out of that hole. And you cannot happily run a deep rear-end cuz then you're outta first gear almost right off the line. Second gear wants 4.10s with that box, but first only wants 3.55s.
My low compression 318 was sorta Ok with it, But it was way happier, by running a deep rear and splitting gears with the OD. Then she really woke up.
I ran 3.09-2.41-1.67-1.30-1.00-.78od-.57od;GVOD in red. That's 7 usable ratios;and
splits of; .78--.69--.78---.77---.78---.73.
I ran that with 3.55s,3.91s,4.30s, and 4.86s.. The final drive with 3.55s (my favorite) was 2.02 in top gear. So 65 was 1630rpm.
But with the 318, the splitting was sorta mandatory, to get anywhere in a hurry.
So that was my winter engine.
My summer engine was a 10.9Scr, HO 367, with a 223* cam, so it had mega-torque. But I got tired of that whole rig-ma-roll, and finally settled on the early ratio, still with the OD unit. Ratios now are
3.09-2.41-1.92-(1.50-1.40)-(1.09-1.00)-.78od, making this a very versatile 6- speed, which I use in several different ways, and most of the time, not at all..
The 230* cam I run now is also happy with the 3.55s. I could actually run 3.23s, but the 3.55s trap better at 93mph in the 1/8th, and also at 65 in second: so me being as lazy as I am, they can stay.
But yeah that second gear is waaaay out there. You have got to rear-gear it right for your combo. And I recommend getting the second gear ratio right, and let the rest be what it is. For me that would be 6.82 or; 6.82/1.67=4.10s,say 3.91s at the least. Yeah, this would make a drag-race first gear of 12.08, but that's how it goes; just rev it up to 3500 in first and when the Revs fall to 1900, live with it. and when you buzz second up to 3500, and the revs fall to 2100, live with it. 65=2300, so that's nice.
The other option is to build the engine from scratch, to use this very wide-ratio box.
The only thing I liked these for was that I could buy them for 50 to 150 at swap meets; about the price of new brass rings, and maybe it had good bearings.
Waaaaaaaaaaay out there
Here's a tip; don't try this box with a 108LSA cam and a low pressure engine; The powerband is just too narrow, and then when the cam falls off the power on the shifts,you'll be measuring acceleration in slo-mo