While I would love to win... and hate to be the bearer of bad news, your raffle is unfortunately illegal. Every state’s laws pertaining to raffles are a little different, but the one rule that’s consistent for all raffles is that they’re specifically meant for non-profit organizations. If Nassau Hobby is a non-profit you could run a raffle by selling raffle entries, but not by requiring a pre-order. You could run a promotional giveaway with no purchase necessary... well you can in most states, rules vary by state, needs to be a game of skill rather than a game of chance in this state and that, a bunch more fine print, red tape, etc... At any rate, they way you have it stated currently is definitively illegal. Running a promotion in your brick and mortar store is a lot easier than including online as it involves many and potentially all states. I'm not a legal expert but have been through the ropes with several organizations both non-profit and for profit. If you want to run a promotion, give away, raffle... get professional legal advice. Unless you expect to get a lot of pre-orders that you would not have otherwise obtained it is not worth it.
It is a lot easier to hope a rumor starts that sometimes some lucky person that orders from Nassau accidentally receives a bonus engine and Nassau tells them to just keep it.