What gene would dilute the red in a black tailed red Maran?

I have a 6 month old black tailed red Maran that has some funky coloring. It’s as though there’s a silver gene diluting the red. There is leakage (more as he matures) on his chest and wings. I’m trying to figure out what color chicks he would throw if I breed him to some other marans and blue egg layers. I have a splash ameraucana and a blue ameraucana as well as a cream legbar, a cuckoo maran and a wheaton maran. I’d like to produce some colored egg layers (easter eggers or olive eggers).