Children who have outgrown the weight or height limit of their rear facing seat, should ride forward facing car seat with a harness for as long as possible up to the highest weight or height allowed by the car seat (refer to user manual or stickers on the car seat).
Proper use /installation of forward facing car seats is as follows:
Harness Straps: at or above shoulder level
Harness clip: always at armpit level
Straps: snug with no slack on shoulder or hip area
Angle: check car seat owner's manual for specific requirements
Installation: less than 1 inch of movement when tested at the seat belt path; use Either a locked seat belt or an approved LATCH position, never both. ALWAYS secure the top of the seat using the tether strap when available. Check both the vehicle manual and car-seat manual for weight limits