NFU are offering 10% off Hilux, £1000 off some D-Max, and 2 or 3% off the Ford/VW pickup.
By the time you’ve paid membership it’s not worth bothering with any of these, you’d be able to negotiate as good a discount with the dealer directly.
Toyota in Warrington are apparently a big fleet supplier - they offered me a pretty good discount as a straight purchase a couple of years ago.
Dealers with physical stock are more likely to be open to negotiation than those who would need to order you something in.