1996 Tacoma A43D automatic transmission trouble really need help.

I have a 1996 Toyota Tacoma LX 4.2 L 2WD and I am trying to fix the automatic transmission. It won't shift into reverse but drives straight just fine. I took apart the pan and valve body looking for anything out of the ordinary nothing. After some research I am inclined to think it is the clutch and brake that control the reverse are not functioning but now iv messed up and did not see exactly how and where the roller pin for the reverse and the balls for the valve checks go upon reassembly and may have lost one of the key straights for the control valves. Where can I find a diagram to assist my reassembly of the valve body

 

I'm having the same problem with my '99, except that it also goes forward in neutral, I'll let you know if I figure anything out.