1-The side of the valve cover has a 5 and what looks like a (p) or (y)
2-The spec plate looks like it has been messed with it says model#FG20 & serial #BET85002
3- I ground down the frame and found BET85002 on the right side frame
4-transmission plate says okamura corp model#Y41153X Serial#5051401
and another number (3) or (8)2001-22032-71.

Toyota dealer by me told me the plate info I gave them didn't check out. So I have spent hours trying to find out what model/generation this dam thing is online by looking at pictures with no luck. I found a lift that looks identical that was a 1984. I also spent hrs grinding paint off all over this lift to see if I would find a serial number that was the correct one. It was painted 5 different times the last coat someone put on it was like a rubber under coat tar you put on cars chassis. So I finally found the number and it matched the spec plate. If some one can give any help on this matter It would be great!!