I was talking to Rimas last night about homemade tubeless tire setups, and he mentioned that he didn’t have a compressor so had a really difficult time seating the tire. I mentioned that I saw a vid of a guy doing it using his car tire and I’d send him a link if I found it again. Found it (@ 4 min 45 sec):
https://youtu.be/AfTfks6iu10?t=4m45s
[video=youtube_share;AfTfks6iu10]https://youtu.be/AfTfks6iu10?t=4m45s[/video]
Seems like a good, last ditch way to do it, but I’ve never tried it myself. If you do try it, pump that car tire back up to proper pressure! 
Or if that’s too sketchy for you, you can try the garden sprayer compressor:
https://www.youtube.com/watch?v=bxNWiLQKxOs