Heater core swap photos

[Malyc]

When I looked underneath, there was coolant all along the underside of the box, with some looking like it came from the vent. I'll take a crack at it this weekend, but are all the nuts/bolts holding it to the firewall accessible from inside the car, or will I have to unbolt it from the engine side?

 

[MC1of80]

There are some from under the dash but the main ones holding it to the firewall must be accessed from under the hood. The studs with nuts.