I am going to purchase a piece of PVC trim from my local hardware store to make my own runners. I am not sure what the dimensions I need are for this though. Could someone tell me what the dimensions of each hyfax runner is? I need the overall length, the width of the runner and how tall each piece is and are these just rectangular pieces or another shape?. Also I think I saw somewhere that the holes were drilled 1/4" from the front and then every 7" from there could this be confirmed as well? Lastly what is used to fasten these to the sled bottom? Thanks guys