The TV (throttle valve) boost valve is held in the transmission body with a snap ring. Brady used a .472-inch valve (middle), which helps increase transmission line pressure without creating overly firm shifts.
After grinding a taper onto TransGo's handy roll pin removal tube, the two roll pins that hold the throttle valve assembly in place can be removed and the assembly itself removed.
Moving to the other side of the valvebody, we installed a "special" 3-4 shift valve (right) rather than the one included in the kit. The special valve gives '87 and earlier 700-R4s the later shift to overdrive that their '88 and newer brethren came with. Be sure to check the directions for checkballs locations; with the balls in place (use a dab of petroleum jelly to secure them), we're done modifying the valvebody.
After making sure that the TV plunger is the correct one (it should have a "94" or no number stamped in the end), the new valve assembly can be assembled (note the small shim, the flat silver spacer, the red spring, and the new valve with its tapered spring, looking right to left). With the TV bushing (it should have stayed in the valvebody) and plunger bushing properly aligned, the roll pins are replaced.
On the right side of our valvebody (as shown in the instructions), we'll make three modifications. After removing the large roll pin and end cap, the line bias valve gets a new, blue spring (right). The old 3-2 control valve and spring (middle) is removed and discarded. The smaller of the two replacement valves, with its yellow spring, was the right fit for this valvebody (left). After drilling two .110-inch holes in this passage, the new valve is held in with a plug and roll pin.
Carefully following the directions, we labeled each hole in the separator plate with the appropriate letter. Depending on whether you have first- or second-style valvebody, holes will be either enlarged or plugged. For the plugs, insert the proper sized piece, lay the plate on a concrete floor, and smack the plug with a hammer. The edges can then be smoothed with a file. When it comes to drilling, make sure you use the right size bit in the right place. Finally, make sure the proper checkballs are also in place.