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Ok, in all seriousness, you need your kit to rev higher. A great way to do that is by increasing the transfer window duration. The ideal way to do that is by raising the entire cylinder up by placing a metal gasket like shim between the case and the cylinder of the height you need the transfer to be increased by and shaving off the same amount from the top of the cylinder, thus keeping the same displacement but having much more aggressive timings.
Your problem is that you already have the exhaust duration maxed out and there is nothing to reverse that, save a new cylinder. It is not the best idea to hack away at the transfer windows, they _should_ be angled in such a way as to best promote cylinder scavenging and modifying them would not be beneficial to overall performance.
So:
Cut weight and re-gear!