Can I make a two port model of this in Spice.

Hi, I'm working on a project which uses a ring modulator. I realize there are chips available that will do this for me, but I think I will build it by hand using 4 diodes and 2 transformers. The trouble is that they are very hard to model in spice. As if the transformers weren't enough. I'm thinking about drawing the schematic in Capture and just trying to make a two port model of it that I can use in a regular .cir file. Any tips on this? Is this a good idea, or not?

**broken link removed**

Thanks
Sean