98 Heater Core Replacement

I found this forum through a mention in a link I found on another site that mentioned there was a how-to on this forum with pictures for heater core replacement. I have found bunch of information but not exactly what I need.

I have my 98 blazer torn apart, but I can't figure out how to remove the heater core housing. I've replaced the heater core in a '97 blazer previously, but the housings are different. Instead of a rear facing cover, the '98 has an upper and lower that I can't figure out how to separate. It seems that the whole thing needs to come off at once, but this requires removing bolts from the front of the firewall that are nearly impossible to reach and behind a heat shield.

Anybody had this problem before? Am I missing something? I'm thinking of doing something drastic! Thanks in advance.

Never mind. I found it. http://www.automotiveforums.com/vbulletin/showthread.php?t=368427

here is another good link with pics, more generic but it could help http://www.sytyarchives.com/howto/viewarticle.php?article_name=heater_core.php&dir=climate_controls