Running discovery 2 td5 on used vegetable oil (advise sought)

I am thinking of running my disco on used cooking mixed with diesel, but not sure on what lengths I would have to go to to prepare it. I have seen a lot of complicated set ups on youtube (usually Americans) but have also seen filterbags for sale on ebay. Do I only need to filter the oil to prepare it? Any advise welcome which will help alleviate the financial burden of owning a disco!

General consensus is that it's not a great idea to use veggie oil in a TD5.