How do I replace my heatercore?

Also to see it being done copy and past link below: http://www.youtube.com/watch?v=z7CimMGCOB8 IF you can change a light bulb you should be able to do that!!

WOW! Not a DIYer kind of job. Have to remove a large portion of the interior dash to get the box out. The heater core is only $100.00 but the labor is a $1,000.00