<< If your ma's Toyota is being junked, then yes, cut the wiring for the Toyota radio out of the dash of the Toyota.
The adapter is probably just called a "harness" in the biz. You connect a replacement stereo to the harness, and that harness just plugs right into the wiring in your car. It's asking for trouble to cut any wire inside your dash, so you use a harness so you don't have to. The harness you buy/find will be specific to the Make/Model/Year of your car, since all car manufacturers use different shaped "plugs" for connecting their factory radios.
Hope this helps.
EDIT: you buy a harness for the Honda. >>
heh yeah it's being junked, i sorta totalled it 😀 So i cut the wires off the one in the toyota, use that to plug into the head unit, and then use a honda adaptor, and wire those to the ones connected to the toyota radio(that i cut off?)?
If it'd be faster to talk, you can IM me at Lithium381, your help would be appreciated.