Remove t-case handle.
Push and turn counter-clockwise spring lever.
Check PU ring under handle half-sphere. If nobody changed it last three years you better had new one.
Close the hole and remove remains of old PU ring.
Install new ring.
Remove rear flange.
Put firstly speedo gear.
Put plastic speedo adaptor and screw it dow with zinc plated bolts.
Put new flange and screw down nut.
T-case with speedo adaptor and new rear flange.
If you have t-case with big flanges (O.D. 104 mm) connect intermediate and front propeller shaft directly to flanges. In that case you need to shorten intermediate propeller shaft for 65 mm. If you have t-case with small flanges (O.D. 92 mm) use adaptors from KIT. Screw adaptors to flanges and propeller shafts to apadtors. In that case you need to shorten the propeller shaft for 80 mm.
Screw down t-case arms to t-case. I recommend use thread non permanent thread locker (usually blue color). Put t-case into car.