SMI is/was the best. I still have it on my HP48 on my desk, use it for curve solutions. Back when I was in the field, I could do anything on it the same as I could in the office: adjustments, calcs, stakeout, whatever. It was an excellent data collector for topo. You were a survey god with a SMI card.
I, also, was a big fan of SMI. I preferred it over TDS, hands down. Used it for many years, the last time was probably when I wrote the Oklahoma test in 2011. I dropped my HP48Gx down the stairs shortly after that - the calculator still works but the card is kaput.
I have the disc, but I don't have an old computer to run it on. If you could burn me a copy on a DVD so it could run on Windows 10, I'd mail the disc to you.