Pin above layouts will make the ball get more length, but since the cheetah and viper have a lot of friction in the back part of the lane, sometimes a pin under bridge with the cg stacked, like a 5 x 5 might work better. Now for the shark, a pin under bridge with a good amount of surface could help, but it could also not hook once it gets to the friction because of the surface and the amount the ball is flairing. One thing that I have seen and heard a lot on here is people talking about doing pin up layouts, like at 4 1/2 and 5 from pap with some surface, the pin up allows the ball to store some energy, but the surface gets the ball to read the lane in the middle where it is needed. But, it depends, on revs, speed, axis tilt, volumn and type of bowling surface. I see the Chameleon as a slightly modified house shot, with less oil in the middle and slightly more oil on the outside. Now pin under bridge could be a good drill for this pattern, but as it breaks down, then a pin up might work better to get a little more lenght and backend as the lane dries up.
Also, your pap of 4 1/4 over is not really a high track, but would be considered more as a lower track, my pap is 5 3/8 over and 3/8 up and I track next to fingers and thumb, so I would be considered as a high tracker. I hope this helps
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