I had never even seen one being fitted when I attempted mine, took 10 mins max and that was reading the book to make sure I didn’t miss anything.
Had 4 mini screw drivers in the 4 holes, put my hand in the tape slot and pulled it out! Unplugged the 2 connectors, fitted the pioneer cage plugged the 2 connectors in, tested the HU to make sure it worked (it did), then slid the unit into the cage and that was that.
(Ohh yeah forgot to say, I needed an aerial adaptor (MK2 PH2 > Pioneer unit))