[KevinW]

suggest: very roughly cut leaving plenty of extra 'overhang;
then try using your wife's hairdryer to preheat the material.
When its nice and warm, then lay it on the area with maximum curvature, and apply more heat - it will stretch. Easier with 1 or 2 extra pair of hands to hold in place. Once you have made it stretch a bit, remove, apply adhesive, apply more heat on non-sticky side, then place on point of maximum curvature. Then, using extra hands, pull gently whilst applying heat from hair dryer. You will almost certainly have to lift and re-0stick it in several places so avoid an instant contact adhesive - the spray on stuff is more forgiving. Once happy, leave for a few weeks. The spray on stuff will probably start to lift, but by then the vynil will have stretched to the desired shape, so impact/contact adhesive can be used. HTH.