According to GPL, every mod posted here, is supposed to have a link to its source. Just look at other links in the post.

Also we enforce that with a forum rule, so yeah, you can take all the elements from all the mods and put them together in the latest release.

But ... there are many problems with that (if it were really this easy probably would have been done already). First, you need to know how to compile it, it's not anything like a lua script. Second, element code may be scattered around, and not many people use github so it can be very hard to figure out what the mod changed. There may be some random code in ELEC.cpp and if you miss this then the element won't work how it did in the original. Third, mods are based on all different kinds of versions, some may be in c++, some may be in c, some may be based on version 40, some version 80. The format of adding elements has changed a ton and you can't put them all together and have it work. So, realistically you'll have to play all the mods separately.