Okay, sorry about that.
As your truck accelerates, the converter isn't using any disc(s) whatsoever through first, second, third or even overdrive until the valve body signals your converter to go into Overdrive Lockup.
That is the ONLY time discs are being used and the only time there is an actual mechanical coupling going on.
"Tow-Haul" Mode for example, simply prevents the converter from "locking up" which tends to keep the engine in a better operating range for towing.
When the converter is "locked-up", it IS using the discs inside the converter either 1,2,3 or even 4 of them.
NOT trying to be condescending here, maybe you know this stuff already (??)
Anyway, the number of discs don't really matter a great deal. Just buy a good converter and carry on.
That would be my advice.