One thing for sure, If you are in a hurry, the greasecar is probably NOT for you. My particular model, the 240 D, was woefully underpowered the day it rolled off the the lot in 1983. This no doubt led to its demise, paving the way for the slightly more spry 300 D and ultra peppy 300 TD. Couple my 67 hp engine with the naturally low octane of waste vegetable oil and you’ve got zero to 60 mph sometime before lunch. However, the upside of the 240D is that the engine is so basic, that even I can fix some of the broken stuff. There’s no pesky computers or other gadgetry to get in the way.
If you want something with a little more gusto, I suggest you look into the VW Jetta Diesel. Looks like a lot of people are converting them.