[Front Range]

These are Toyota Previa Minivan seats, they might give you an idea of where a lower back will sit (minus curved headrest). They still won't allow me to have full leg extension but are comfortable enough for long drives. The curved back and bottom gives a bit more room but the seat back still touches the glass at the headrest. There isn't much room in the pickup cab to begin with though.

I looked at the same seats you bought, just couldn't afford them. They look good in your truck.