Go to your local, well-stocked auto store and buy a good vinyl repair kit. You can custom mix the required color, and they give you a set of texture sheets to match the 'grain' of the vinyl. The really good sets even have a heat iron to speed the cure.
I've used them and with a little practice, you can match the look and feel of the liner and make the cracks go away!
Solar Tech Energy Systems, Inc.
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