Ok I have one male in a 100 L tank with 7 different plants and bogwood and loads of hiding spots and another male in a 40L tank which is also planted but not as well as the other.
In my view, the 100 litre (25 gallon) aquarium, the largest, will not house two males with females, at least not for long. It would be good to get all four together though, to see if a pair forms. There are a couple ways to do this.
The perhaps "safer" way is to add the two females in to the 100L tank with the existing male and see if a pair forms. Both females might be OK in this tank, but I would not really expect this; if one female does bond with the male, the other female will probably be driven away, and as there is not much space, this can get rather rough on her. You could then remove her and leave the bonded pair.
Another option would be to put all four fish in the 100L tank, and again watch for a pair to bond. My only caution here is that the male already in the tank is going to consider the entire space "his." This is just in the fish's nature. If the tank aquascape is thick enough that it really breaks up the space, sometimes the ram will form a smaller territory when others are present from the start. But if this male has been in the tank for any time over a couple weeks, chances are his territory is well established; the second male's appearance may well be his end very quickly, though individual sometimes surprise us.
I have a male Bolivian Ram in my 5-foot 115g tank, and he is the only cichlid; the entire tank is "his," without question, and he is certainly in control and all the 120+ fish (various characins and corys and whiptails) know it. I added a lovely female once, and they seemed to bond, as they spawned four times; but I thought that between spawnings and even during, they were not quite "normal" in their attitude, and after the fourth spawn he decided to drive her out of his space, and she ended up dead in a day or two. I didn't understand the "bonding" back then, or I would have removed her. I've never even tried another mate, he is now six years plus in age and will live out his life in his own space unmolested.