Holley is having a newsletter sign up disguised as a car give away drawing, for this Mustang, winner announced in 2016 (but really, you are signing up for their newsletter to spam your email)

If you fill in the entry form, you then get an email that states "
Black Heart Mustang Giveaway Please Confirm Subscription Yes, subscribe me to this list.

and SO I asked what the hell is this bullshit? I entered a drawing, not a subscription. Alex Healey, Content Coordinator, Holley Performance Products, replied:

The subscription puts you on our consumer e-mail list, which means you will receive one monthly newsletter e-mail from me. This newsletter contains articles and videos focused on Holley events, new products, racer successes, and much more. There will be no spamming and we do not sell e-mail addresses. Once you receive the first newsletter, you can unsubscribe 

He is oblivious to the obvious that his newsletter IS SPAM and not an entry for a give away car, so, now you know. Enter knowing the real deal, and without surprises

The winner of this giveaway will not only receive a 2015 Mustang GT, but all the parts needed to turn the car into The Blackheart Mustang.

This includes a set of Hooker  headers, a full stainless steel three inch Hooker exhaust system, an Airaid® intake to supply cold air to the engine, and a Diablosport® tuner to unlock added power from the intake and exhaust.

Plus, a custom NOS® application specific nitrous kit for the Mustang’s 5.0-liter Coyote engine to put even more power on tap.

Little needs to be refined concerning the interior and driving experience of the 2015 Mustang GT. Even so, the Hooker team is throwing in a shifter kit from MGW, along with a set of Eibach lowering springs for a lower stance and improved handling attributes. Win the car, win the parts and get in the driver’s seat of The Blackheart Mustang.

The winner of the Hooker Blackheart™ Mustang Giveaway (and a guest) will be flown to the Holley Performance Products' headquarters in Bowling Green, KY to take delivery of the car and will be treated to a parade lap around the new 3.5 mile NCM Motorsports Park road course.

https://www.holley.com/blog/post/hooker_blackheart_2015_mustang_giveaway/

This seems to be straightforward, you fill in your name, address, email, and that's it. One entry per address.