Because that’s a very basic filter, yes you can just install it & the tweeter using the OEM wiring. The OEM tweeter mount is oval ish shaped though, so you’ll have to make a bracket or use lots of packing material or w/e to mount it. You’ll also have to bodge something to go from the OEM renault plug (same as the door/mid speaker) to a male spade connected to be able to plug in the tweeter/HPF. I’d just buy another pair of adapters, remove the female spades and buy/crimp on some male spades.
If it was a filter box which output a band or low pass signal for the mid AND a high pass signal for the tweeter, then this is the point at which you need to route new wiring to use the filters as intended.
p.s it sounds overly complicated just because that kit is designed for a car where the tweeters are also in the door and can be be connected directly to the mid.
