Heater Core :/

[ptrain]

Hi guys,

I suspect my heater core is leaking. I'm getting a little dampness in the passenger foot well. I'm still not sure if it's coolant but I think it is. It hasn't rained in a week...

Have any of you attempted a replacement? Any tips on how to do it? I have the service manual here for the car but I can't find anything on it. Is there a decent stop leak product could save me some hassle?

I've taken the glove box out and the centre console but I still can't really see anything.

Car is a 99 rezzo ga15 hatch
Thanks,
Peter