Getting competing quotes is a good idea. So would be checking TrueCar, Edmunds, Kelley Blue Book, etc. to see what prices in your area are really like. For us in the south western corner of NH, going north or over the border to Vermont can sometimes give us better pricing so check further afield to ensure the local big guy really is your best bet (they may get volume discounts but has way larger overhead than smaller dealerships).
Some dealerships give the best price, prior to face to face negotiating, to their online customers. While there is a bit of a push to clear off 2018 models before the new ones come in, he might actually be in a better bargaining position simply by choosing the end of September to buy --- it's the end of the month and end of a quarter where dealerships and salespeople are somewhat more incentivized to close deals to help hit targets for bonuses. If he's bought with them before, he should get a discount as a returning dealership customer and possibly the same from Ford if he's staying with their products.
If he's trading in his old vehicle, make sure you know it's worth so he gets a good deal on that end of it. And even though he might not need it, run the numbers to see about financing if he qualifies for 0% financing which might get him some other discount as well (just be sure to note if there's penalties for paying it off early and any other gotchas). Least likely, but if he hems and haws while talking with the sales guy because of the recent safety recall, maybe a nervous salesperson will take a little more off to calm Dad's supposed nerves.
Best of luck.