I managed to make out the plates i think.

STYLE No 51/5211B
BODY No 259
TRIM No 2-195
PAINT No 253-15915
TOP ACC 7

That was the only plate readable. i hope this can help.Also, i found a brochure of a mapleleaf on the net, it was 48 and it had window vents to, so did they just maybee have it different to the Chevs? i dont know much about it