Yes, you can play with the cals in MP Tune. The files are posted on my google site (calsbyshelgame, just search google for it).
I was going to make cables, but honestly, the response to me being able to make cals has been so lukewarm I'm not sure I'm going to bother. It's a big investment to buy all the parts to build the cables and I'm not sure if they would sell. I bought a bunch of cores thinking I would be able to make cals and sell them, but I've only sold 2 since Feb. Everyone has told me that my cloned MP computer is cheaper than what you can buy a used MP for; and then everyone asks for dyno 'proof'. Like I'm going to go to a dyno to show that I was able to clone an MP computer and raise the rev limiter...
I think my time is better spent making stuff for the older turbo cars (like the SuperLM). Dealing with the general Neon population has left a bad taste in my mouth.