@elliottnewcombjr
Don’t Skip a Center Speaker, even if it has to be small, or behind something, try one
There are very good reasons for not using a centre speaker, especially one which is in effect a horizontal d’Apolito array! As soon as you move away from dead centre, the outer drivers create an interference effect, or comb filter. If your main front left and front right speakers have good imaging capability, let them do what they are already good at.
Your pre-processor should just add the centre signal to the signal for the two front speakers - my Marantz ones all do this. My main system is configured with two main front speakers, and two rear speakers, plus four ceiling speakers and a subwoofer.