Water injection setup advice

[T5REU]

Just opened up the box containing my second hand water injection kit. It's a coolingmist, system I think lol. Not sure best place to house the bottle or any of the gear. This is what come. I'm Crap on engine stuff
Extra wiring and relay not sure what for

[T5REU]

[T5REU]

Can't get hold of the lad who I got it off lost his number. He said home made loom was for boot lid fan to switch on dash. Not sure what that means.. Single red in sill goes to door switch for alarm. What's he on about? These r his notes he left on the box. Twin grey for led. God I'm lost here. Not sure what pipe connect to charge pipe here.