Me, I would want that in writing. Hey if your truck isn't perfect and as ordered, I will rip up the paperwork. I have been in this business for 16 yrs and have seen shady sales people (managers are the worst) and its hard to believe anything. Even the finance guy I dealt with when I bought my 21 seemed like a cool guy until I realized he was trying to fk me hard on the add ons for his own benefit.
There is virtually no risk at all to signing the paperwork in advance and then the truck being not as expected. Laws differ state to state, but they all revolve around "taking delivery". No matter what anyone tells you, that truck is not yours until you drive it off the lot. If you were to show up and have all contracts signed but something was not right, you can simply "reject" delivery. If the dealer did not agree that there was something wrong with the truck they could try to sue you. But, If you reject the vehicle the burden is on the seller to show that there is no breach of contract. If there actually is something wrong with the truck that is breach of contract, it wasn't in the condition agreed upon, and the dealer would have the chance to "remedy" it.
Legal details aside, just know that until you drive the truck off the lot, the paperwork means nothing. Even if you were the one in the wrong, (IE the truck is as agreed but you changed your mind before taking delivery), the dealer could sue you and they would be in the right....or they could put the truck on the lot and sell it tomorrow morning while keeping your $1000 deposit; which do you think they would chose?
The paperwork says exactly the features you ordered and the condition is new which means there can be no damage whatsoever. The contract literally is the writing "hey if your truck isn't perfect and as ordered, I will rip up the paperwork". The paperwork is null and void if the truck is not delivered to you in the condition described in the paperwork, and if you claim that the truck is not in the condition agreed on the paperwork, it is the dealers burden to prove that it is.