Looking for Wrigley Field Seating Charts from late 1960's and 1970's

[hardware303]

Anyone have a Wrigley Field seating chart from the late 1960's and/or early 1970's that they could share (or point me to a link)?

I'm a ticket collector and have picked up a number of Cubs tickets from that time period but there's a slight wrinkle. These days seats at Wrigley are identified by aisle (then row/seat), and back in the 60's and 70's it was instead by section (then row/seat). The current-day aisle numbering scheme skips some numbers in sequence (e.g. 18, 20, 21, 23, 28 and 29 in the lower sections), and as luck would have it some of the tickets I have are in sections identified by those missing aisle numbers. Yes, the general seat location seems fairly intuitive, but I'd like to have a seating chart from that time period just to confirm.

Thanks in advance!