First place I looked was Snugli's website (now owned by Evenflo) to see if they had instructions there and if they didn't have them online, was there a contact number or email for them that I could use. I did find a 1-800 number and I called them (via Skype, because even though I live in Finland, using Skype to call 1-800 numbers is free!). The lady who answered my call was nice, but because this Snugli model is so old, they don't have any instructions for it and she wasn't able to find them online (from their own personal site?). Also, this version of the Snugli is too different from any of the current models for the new models' instructions to be of any help, so the lady said. I thanked the lady and said goodbye.
I next started Googling to see what I could find. It only took a couple of searches for me to find two potential hits. The first hit I found was a similar looking Snugli that had been sold on Etsy. I book marked this in order to come back to it later if I couldn't find anything else. The second place I found was a chat forum post from earlier this year where a lady's husband had found her a vintage Snugli at a second hand store, still with its original package and receipt! I signed up to the forum and private messaged the lady in hopes that she'd reply to me. And what do you know, in less than an hour she had replied and said she could scan the directions for me. How cool is that?!
I am now waiting for the instructions to arrive in my inbox. I'll keep you updated!
Edited: I have received the instructions. If anyone out there needs them, let me know and I can forward the pdf to you.