Roll up to any quick lube on a weekend evening when business is slow and the "manager" is gone. Produce a box of doughnuts, and just ask them if they could do a quick drain and replace with your own fluid. 5$ for 12 doughnuts, done. Chat'em up a little about how you're going to put a turbo on it and "chip it" while they're doing the swap. I worked at a few of these joints a million years ago. We would do anything for a little bribe.