/ about factory deck vs aftermarket

I've got a 2016 ford f150 alt and I have my system components which consist of a zapco dsp z8 ivii, a zapco stx sq 6 channel full range amplifier for my mid bass mid range and tweets, and a zapco 1650 for my sub,ive got the factory deck and im wondering if I can use the 2 front left and right speaker outs to connect to 2 rca low level inputs into the dsp?or would it be better and easier for me to just get an aftermarket deck that will allow me to retain my stock deck features?if im not making sense I apologize and will try to explain better.thank you for any guidance you guys can give

Keep the stock. Why do you need low level inputs? High level on the 2016 f150's are flat signals on the front and clipping free up to about volume 28.

awesome, thank you