Untaxed fuel, used motor oil, and on-road risks

I only get on every few weeks to be able to post followups just fyi.

Would I get in more trouble for having ATF fluid or motor oil in the fuel tank than ag fuel? :- P Or even for running some kind of veggie oil if I showed I were keeping logbooks of the avoided taxes to pay to our loving and useful government?

I guess I have to wonder what would happen vs the example above, where if I was 'legitimately' running either ag fuel or "something other than pure road diesel" while off road, then on the next fillup on the road i'm on road diesel. I would be running a truck for a farm/ranch though i'm not sure if it would have personal vs farm plates (it would not be in normal For Hire commercial usage at this time) but even if I followed the rules it might not be worth the risk.

I'm wondering if they would be equally dickish about even cleaner fuels like if I was running CNG... as in ALOT of CNG. (i've heard up to 85% mixes running in unmodified diesels) AKA how much is state tax dickery, how much is EPA 'letter of the law' dickery (even if cleaner youre fined because it isn't stock), etc.

Strangely enough it actually was a detroit, swapped into an even older Mack body, I remember the rocky mountain hummingbird sound. Detroit 2 cycles had low pressure unit injectors which were incredibly resilent to feeding it fuels that would crap out even other lower pressure mechanical injection engines because there was no injection pump. The only thing more durable is probably the military truck multifuel 'Continental' 6 cyls. Obviously it would be dumb to even consider waste fuels on any truck of the electronic high pressure injection era. It's something you do on the farm beater youre running until it dies and couldn't sell for more than $800 anyway.