Ahh, if you've taken care of that I can't be of much more help - I've only ever tinkered with heater cores on a 1G and like you said, those clamps/hoses are a real PITA after 20-30 years of being baked in place. Silly question, but do you have a factory service manual?

https://www.scribd.com/document/17887620/97-99ECB is the 2G manual. Section 55-24 (55 in general) has the heater core assembly but it really doesn't show much in the way of attachment points for the core itself.