Ricoh A172 Service Manual page 137

[B]
[A]
14. Adjust the height as follows.
1) Place the film position sheet [A] on the exposure glass, aligning it at
the rear left corner.
2) Put the mirror unit [B] on the exposure glass by aligning the holes with
the positioning pins [C] on the lens cover.
A172/A199
[C]
3-48 SM