Provide a good quality mic with a stand along with a GOOD clean DI box. Setup the gear the way you want to and tell them you would like to use both. I have gotten good success from doing that. Explain to the sound guys what you like to do tone wise with a NICE/PLEASANT voice.
The cynic in me can't help but think the sound guy will give you a big thumbs up and you'll be happy, while the cable from your mic will be lying on the floor next to his foot, unplugged.
