First things first, all you need is third to clear the menu book. After that, tuning is your friend, and I'd start with the transmission as top gear on both the Tundra and F-150 is way too high for racing. How much tuning you need depends on your drafting ability, and possibly the difficulty level you're on.
Looking over my log for the Plus account, I was able to win with the Tundra on normal difficulty just by sticking a full-custom transmission (non-race version) on and auto-setting it to 250 km/h. The high close-ratio transmission might also work if you want to save 9,000 Cr. If memory serves, I was able to eventually get the F-150, but not the Tundra, down to no tuning but a bit of blocking.