Relocating pedals

Not sure if this is in the correct sub forum. I’m looking for good options to relocate the pedals on my son’s kart, I used the Carbon Footbox in his first season 2 years ago, and last year with a newer chassis, I just removed the stop screws and leaned the pedals back as far as they could go, that just managed to mess with the angle and geometry of the pedal travel, so I would like to properly move the entire pedals back towards him, and also add some heel rests. What are the best options available to purchase, or has anyone designed their own? I’m getting close to just designing something from scratch and making it.

Comet Kart Sales as well as others have several relocators and extenders to choose from.

Most just bolt on to the floor pan or the pedal itself.