When I was playing about with modding Civilization III a few years ago, I was also playing the game Deadlock II: Shrine Wars a bit, as well. As it had a large amount of technologies with art around the right size, I thought that I may as well go ahead and make them usable in Civilization III. Earlier this year, I realised I had not converted them to the correct 256-colour palette and so set about doing so with the help of Gray Wolf's tutorial, and at the same time added the extra Time Dilation technology to the set.
These have been sitting on my hard drive for a LONG time (apart from Time Dilation), so I thought that since I've now joined it was about time I released them. Hopefully someone is able to find them of some use! The art in the in game manual for Deadlock II is a bit stylised, but I don't think that means that you couldn't fit at least some of these somewhere. I've only tested a few of them in game, but they looked fine, so there's no reason as to why the rest shouldn't work.
If you do use some of these, please make sure that you credit Cyberlore Studios and Accolade for them, as they originally made and published the Deadlock II game.
Deadlock II Tech Icons 2016-10-05
Deadlock II Tech Icons