"Can I cause any damage just popping the hoses off?"

Yes, you can ruin a heater core. It's safer to cut the old hoses off.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.