The installation instructions with most base plate kits is usually well done. Your nephew should be able to do the install. The tail/stop/turn wiring should probably be left to the professionals. It requires running the wires the full length of the car and adding diodes. The aux brake will also require some wiring.
On your C-RV there is a fuse that needs to be removed every time you toe the car. That will get old very quick. There are kits that replace the fuse with a fuse and switch, so all you have to do is flip the switch when you get ready to tow.
Are you aware of the transmission procedure you must do every morning? Start car and run for 3 minutes, put transmission in drive for 5 seconds, put transmission in neutral, turn off engine and tow. DO NOT put transmission in neutral from any other position before towing.
Richard
2013 CRV