Did you go with a manual VB or trans brake?
With the couple mods to the VB i made, it'll hold manual 1 and 2 forever until i upshift and in 3, shift on its own now.
Setup the same as my suburban's 700r4.
I like it that way, may change to full manual eventually, but i guess this, for now, is "semi manual"
I decided against the transbrake, because of how it shortens the life of your front pump when you're doing anymore than HAULING ASS. (Haha)
Sitting at a light, or drive thru, or cruise in, whatever, it's always maxed out on fluid pressure. Theres a sort of valve i think i can buy that limits pressure, and i can dump it when i launch the truck, but that was gonna be another.... 700-800$.... so... for now i'll hold off
This will be a hard shifting SOB that should smack gears really fast.
3rd is dual fed properly, 1st and 3rd gear has 6 clutches each, 2nd is 4 clutches, all clutch drum tolerances are set fairly tight, but safely tight. Red eagle clutches, regular steels, no waves for shift softening, 1-2 accumulator has been modded for a hard shift effect. Kevlar bands, upgraded 34 element spruage direct drum. No walk tailshaft bushing, boost valve in pump, every seal and bushing replaced, drums air checked for apply, etc etc, and with a B&M shift kit which essentially comes down to check balls and drilling out the seperator plate for a higher fluid flow to the fwd gears.
Im no expert, but this will be a mean sob.