to replace a heater core in f150, lift hood and remove both coolant hoses near firewall
then inside truck, remove ashtray this will enable you to get at a screw that holds glove box in dash
remove glovebox
then behind glovebox is a black plastic panel
remove screw holding this panel
remove panel, you will then see the heatewr core
remove screws holding heater core
remove heater cre
istallation of new core is exact opposite to removal of old core
when all reassembled, check coolant level, as you may have lost some during replacement of core