Well, I've found a source for waste vegetable oil. Or at least, a source that doesn't mind me dumpster diving behind their shop to grab their used oil. I didn't have enough tubing at the time to draw any oil, but the remnants that I saw in one of the buckets looked clear and amber, which is apparently the way it's supposed to look.

In the next week or so I plan to grab 5 gallons of oil and begin the process of letting it settle and then prefiltering it. My plan through the winter is to run an 80/20 blend of #2 diesel/WVO. That's a fairly conservative blend, but I am not making any modifications at this time to ensure proper heating of the fuel or the fuel lines. I will be plugging in the engine block heater every morning regardless of temperature to ensure I'm not injecting VO into a cold engine (which contributes to coking).