Thanks guys! We were able to get all of the straps off in preparation for todays first Belt Positioning Booster ride.
However still a question about LATCH. Gain, this is a Eddie Bauer high backed booster. Not sure of the exact model. I've been researching and finding conflicting information on whether or not its safe to use the LATCH system along with a seat belt. A lot of it seems to depend on the weight of the child and the seat itself. Since we no longer have the manual, Im unsure of the best way to put the seat in the car.
No, with this seat you do not use the LATCH system while in booster mode. The weight of the child is irrelevant. The LATCH system is only for the seat when it is in harnessed mode.
You use the seat by resting it in the passenger seat, placing the child in the seat, and strapping the belt over the child, which holds both the child and the seat in place.
A word of advice: it's extremely important that you only ever use this seat in booster mode. Continuing to use it in harnessed mode is extremely unsafe because the child has substantially outgrown the limits of the seat, which could lead to catastrophic failure in an accident.
However, this particular seat ALSO tends to make a very poor booster. It causes the lap belt to rise too high on the child, which can cause serious internal injuries in a car crash.
Using this booster is better than nothing, so you should not discontinue use. However, I strongly suggest purchasing a different, dedicated booster seat for the future. The Graco Turbobooster is affordable, fits most children very well, and is available in places like Target and Walmart. Don't forget to put the screws in the armrests, they're mandatory!