how do I remove the heater core?

(97 tuarus 85,000 miles) I had little to no heat so I removed the water pump but found it was in perfect condition. I check the hose to and from and found them to be clear. I tryed to run water thru the heater core via the hoses and got little to no passage . . . so i can only assume that the core is pluged. I dont think forcing water thru will clear the core ? so how much truble is it to remove the core, I see in the hanes book it talks about the instument panel but the core is more to the passanger side . . . im confused . . . anybody here expericed the removal ?

I came across this when I thought I would have to replace mine.

http://www.airsept.com/Articles/RecycleGuard/macs_SR03.03.pdf

I had more success flushing the heater core from the water pump side with a hose than I did from the thermostat side.

thanks for the web site it helped a lot. Am I correct? . . . . I do not have to open the A/C lines to change the core?