Upgrade your soft-shifting auto with a shift kit.  These kits fix and prevent inherent problems and sloppy shifts with upgraded valve body springs and seals.  transmission removal not necessary. 
You can choose to eliminate the accumulator pistons in the 1-2 and 2-3 shift as well. 
Very nice upgrade to compliment modified, as well as stock vehicles.
HD version also available, requires trans removal.

Popular kits include:

Nissan Skyline R32, R33 and R34 Tiptronic and non-Tiptronic
Nissan Terrano/Pathfinder/Mistral Auto
Nissan Laurel, Cedric, Gloria
  RE4R01A, RL4R01A, RE4R03A, JR403, RE4F02A, RL4F02A, RE4F03A, RL4F03A, RE4F03B, RE4F04A, RE4F04B    RE5R05A, RE5F22A  
 
Toyota
Supra, Soarer, Chaser, Mark 2/Cressida, Cresta, Landcruiser, Hilux Surf/4Runner
 A340, A341, and A343    A245E, A246E    U150, U151, U250 E and F    U140, U240, U241 E and F    A750, A760, A761, AB60, A960 “E, H & F”    A650    U660E    U760E

Subaru
Legacy, Forester, Impreza
4EAT, R4AX-EL    5EAT, RE5R05A

Mitsubishi
Pajero, Challenger, Delica

Allison 1000-2400 Series    KM175, KM176 and KM177    F4A22-2, F4A23-2    F4A-33, W4A-33    RE5R05A    545RFE    42RLE    A500    JR403

Please contact us for pricing.  Provide vehicle year, model, and transmission code from the ID plate.