Deve,
I also set up my rebuilt OD to work as the factory intended. COSMO can provide you with a darn good list of reasons to introduce a manual switch, providing the true split-shift capability. But, I was intrigued by the way the manual described the theory of operation and how 'automatic' the connection between the driver and overdrive could be. Nobody knows that manual more than you do, but I was really taken in by the thought that went into how and when these OD units work. I do not regret putting it back to factory setup and have been enjoying my truck ten times more with the OD.
1st is too low for my ratio to be effective in OD (3.90 rear), but I will 'allow' the trans to shift into 2nd over when running around in town (by simply lifting my foot off the gas after 28mph). Most times, though, I keep slight accelerator pressure until I get to third, then I'll let it drop into 3rd over. Sounds like the engine goes to sleep, it's so much more quiet. I love it.
As for converting to floor, I can't see any reason why that would not work. None of the mechanicals interact in any way with the column shift, top to bottom. Other than making sure the shift lever patterns don't change (so the reverse lockout rail operates as before), there's nothing to think about with the transmission side. All the electricals are independent from the shifting mechanism as well. I reconnected my kickdown switch as intended, but again, that's on the carb and totally independent of the transmission levers.
I say 'go for it!'
Jim
