instead of using wooden blocks use a cheese wedge style block and jam it into either end as far as you can go so the pressure on the top and bottom ski is evenly distributed.
^ya that's my only regret. when I took them out they bent up but there was still camber farther up the ski so it kinda evened out. It's alright though I'm fixing that I've just got a bigger block of wood higher up on the ski and I'm heating up the whole ski. It's working just needs 1 or 2 more heatings