I recently purchased a 30 inch cooktop and was informed by the installer that the opening in my counter was too large - I had a 30 inch in the space previously that did have a little space around it but did not interfere with my usage, however the installer informed that the opening cannot be larger than 28 1/2 by 19 3/4 and the opening in my counter is 29 7/8 by 20 1/2. Originally it housed an old GE which is no longer being made and the 36inch cooktops are too large - Even the few 32 inch cooktops are too large - I need about 1 3/8 inch buffer on one side and 3/4 inch on the other - any suggestions.