Can I make graphviz concentrate edges based on color?

I have a directed graph where the color of the edges matters:

Current Diagram

digraph {
    splines=ortho
    node [shape=box];
    1 -> 4 [color="#51dbf4"];
    4 -> 7 [color="#51dbf4"];
    7 -> 1 [color="#ac043e"];
    7 -> 1 [color="#51dbf4"];
    1 -> 7 [color="#ac043e"];
}

I want to combine the maroon colored arrows to make the graph more clear.

Desired Diagram

digraph {
    splines=ortho
    node [shape=box];
    1 -> 4 [color="#51dbf4"];
    4 -> 7 [color="#51dbf4"];
    7 -> 1 [color="#ac043e" dir=both];
    7 -> 1 [color="#51dbf4"];
}

However, this requires me to manually change each arrow that needs to be combined into a double-headed arrow. I wanted to merge these automatically. I tried using concentrate=true to make the arrows merge, but that kind of destroys the meaning of the graph:

Incorrect Diagram

digraph {
    splines=ortho
    concentrate=true
    node [shape=box];
    1 -> 4 [color="#51dbf4"];
    4 -> 7 [color="#51dbf4"];
    7 -> 1 [color="#ac043e"];
    7 -> 1 [color="#51dbf4"];
    1 -> 7 [color="#ac043e"];
}

Graphviz insists on merging the arrows regardless of their color, which is not correct in this case because it kind of just obliterates most of the edges.

Question

For my use case, I have a large, code-generated graph with tons of edges and I don't want to manually change so many edges to be double-ended. Is there a way to specify to graphviz that I only want to merge edges of the same color? Like maybe I could tag each edge with a group ID and then it would only merge edges that have the same ID? Any ideas are appreciated.

There may be an easier way, but this gvpr (http://www.graphviz.org/pdf/gvpr.1.pdf) program does what you want.
For each edge, it checks if a "reverse" edge exists, and if so checks if both have the same color.
If so, set dir=both & delete the "reverse" edge.

E{
  edge_t N2;
  N2=isEdge($.head, $.tail,"");
  if (N2!=NULL && N2.color==$.color){
    print("// bingo : ", $.name, " <--> ", N2.name);
    $.dir="both";
    delete($G, N2);
  }
}

And a (Linux) command line of
gvpr -c -f single2double.gvpr myfile.gv | dot -Tpng >o.png
Giving: