I would still go with the temperature then you need to raise the basking light and get the temperature down , but I would still try a digital thermometer to double check.
This is the one I bought, you can place the thermometer at the cool end to get your readings then the probe under the lamp for them readings, one thermometer to do the two reading for you
http://www.ebay.co.uk/itm/Digital-FR...#ht_950wt_1186