You shouldn't have had to cut out any plugs for the loom? I got mine out complete! You can unplug the door connector with an 8mm socket then pull the plug into the car then the speakers are on a seperate plug within it that slides out, never mind it's done now
Sod that I'm keeping my heaters lol I'm not going that hardcore on mine. Lost all the sound system but will still have a dash and heaters and even aircon mainly because I'm thinking of Nurburgring in 35 degree heat!