What is the best way to get an overdrive auto in a 67 Barracuda?

I (personally) wouldn't enjoy shifting gears (gear splitting) all the time. I'm a simple guy with simple needs!!Treblig

I didn't either, and my cam was a lil big for the OD's splits. So I now have the 3.09 low box with GVod tacked on. I can still shift exactly as before, cuz the splitter still works the same. But I don't have to, cuz the factory splits are almost perfect. So; now, I have 8 useable ratios,of which I never use more than 5, but not necessarily the same ones.
The new ratios are; GV in bold
3.09-2.41-1.91-1.50-1.40-1.09-1.00-.78od
1)When I'm in a hurry, I use the first four; 3.09-2.41-1.92-1.50,which,with 3.55s will get me 110@7000, and then I stuff it into either direct or od.
2)When I'm tooling around I use the main box; 3.09-1.92-1.40-1.00.
3)When I hit the hiway, I use the first three in the main box, then split into 1.09 to finish the run to the speed limit, then into 4th in the main;
3.09-1.92-1.40-1.09-.78 -I call this the short 4th/long OD.
The 1.09 short 4th is a swing gear, sometimes I use it, sometimes not.
The starter gear is 3.55x3.09=10.97
The hiway gear is 3.55 x .78=2.77
4)Oh I almost forgot my favorite; cruising around at 2800 is 33mph in 1.92 second gear. That gear will get me to 65@5500. And the fast way there from a stop is 3.09-2.41-1.92.
This set-up has by far, been the most enjoyable.

But I have a confession to make;
Would I do it again?
No.
As many bases as this hits, I often wonder if I might get as much or more pleasure out of a straight 5-speed.
And if I could afford a do-over, it would likely be a 408/700R4,or a small-cam360/5spd M/T.Or a small-cam408/3.23/A833od. Or a.......
So for you guys that have done the 408/700R4-I'm just a little jealous