Tried to find any info about this and found this description:
"On the right side from the back, seen from the outside, you will find a long number molded into the plastic, the last two numbers show which year model it is."
They started doing this in -94 so sadly anything older would be guesswork.
I looked through these old catalogues but sadly your model was not mentioned
https://cremoboats.se/aldre-kataloger/