ok i faced the dreaded heater core problem replaced heater core in my1989 ford mustang and here are the short cuts different then the 6 hour job everybody post on internet first disconnect neg battery terminal then remove passenger seat 4 bolts remove console armrest first then rest of console then remove all dash bolts from bottom of dash remove glove box door then now the dash will be free to move dont remove dash heater control or the instrument cluster nest go under hood drain coolant half way down in radiator remove heater hoses then remove refrigerant lines next remove two nuts holding heater box on firewall under hood then pull passenger side dash out about 6 inches and propt passenger side of dash up with a piece of 2x4 3and one half inches long the drivers side dash will be down and you will lift passenger side of dash up with 2x4 propt up on passenger side of car just outside car passenger side of dash will be then lifted up almost to top of windshield then pull heater assemble box out about 4 iches then take 2 bolts out of heater box on top to remove heater core wiggle old core out then put in new core put dash back together then put console back in then hook up heater hoses and refrigerant lines fill radiator back up and check for leaks already did this proceder took 3.5 hours and that was taking my time i told all of you i would find shortcut and i did this works perfect no more 6hour heater core jom contact me at donalddorsey@yahoo.com for questions thank you hope this helps you