No problem. But I've pretty much reached the limit of my knowledge, and ability to puzzle things out from first principles.

I haven't designed any digital logic hardware in literally about three decades, so I know little about the current state of the art in logic simulation software. A quick google on "logic simulation software" turned up the usual millions of hits, but the first page had several hits for free software that looked pretty competent. Non-authoritative list: Simulo and LogicCircuit caught my eye as looking fairly easy to use. But I don't have any experience with them, and all marketing material makes the product sound good. Caveat bullshit.

A "3 input" IC might be referring to trinary rather than binary logic. The three states could be something like +5V, 0V, and -5V. I don't know of any hardware like that in the real world, and don't know if the software could do it. But you might be able to simulate it with binary using two bits and some gates that turn on in response to three input patterns, say 01, 00, and 10 to represent the three states. Notice that 11 isn't used, making this encoding only 75% efficient.

Good luck, and post your results here so we can take a look.