Grand Theft Auto: San Andreas – The Definitive Edition

Pretty easy one on this version of the game, personally I did this just after buying the airfield.

Steal a tank by entering area 69 through the smash able chain link fence in its perimeter.

This gives you 5 stars, head over toward the airfield with the large hanger garage, take a few cop vehicles out on the way if you don't have the 6 star achievement, stick it in the hanger and save.

Pull it back out now you have 0 stars and start the mission from the airfield, reason for this is that most of the targets will appear around bone county and the Vegas stadium and freeway areas, nice open terrain means you can keep the tank moving quickly from target to target.

You start with about 5 minutes, time is given very generously for completing each level so don't sweat it if you crash etc.

Took me about 10 minutes to get to level 12 all in, the target vehicles are also a lot slower now than on the original even when they get spooked they seem to slow down again, I'm assuming this is to cater for other ported versions of the game.

I remember on the PS2 I would favor use of the hunter for this type of task because I'd just blast missiles at the cars are grouped together each level, now in order to have access to the Hunter military helicopter you need to get gold in all tests of flight school, if you can manage that then Hunter will be at airstrip (you may have to leave and come back for it to spawn). Then just get in, fly up and trigger vigilante in the area so that way you're in dessert area.
Now do note that this is not necessarily going to be easy for everyone because you will need to be good with flying a helicopter and shooting missiles and eventually you'll have a high wanted level and can't just go into a pay and spray unless you want to land by one, find a non-cop vehicle, and do such. I personally managed to get 12 levels and pop the achievement but unlike the others (taxi, firetruck, paramedic) the levels kept going and I was already in a mayhem mood (KILL THEM ALL!) so I kept going and blew up at the end of level 18 flying through a casino on the strip. But still go achievement and a lot of money. So helicopter, tank or old school drive-by shooting and ramming your car into criminals, you have your options :)