Transgo makes this kit do exactly that, so no computer controllers needed. From TransGo: Off-Road, Competition, Pro Street type shift kit will convert your 4L80E to a stick-type full manual transmission. This conversion will make the transmission a stand alone unit - no longer requiring a controller or computer. This modification will defeat the lock-up. Customer should contact TransGo directly for additional instructions regarding converter lock-up. Notes: Stick shift, full race, competition, off-road and pro street. Full manual control. https://www.summitracing.com/parts/trg-4l80e-3
Eliminating the lock up converter is taking away one of the largest benefits of running a modern trans. Wiring a standalone computer is really no problem these days.
