Want your old mods before the SteamPipe update to be used afterwards? Well, you've come to the right place.
In this example, I will change the Health Plus meter to another one.
http://i.imgur.com/Jx67XoB.jpgFirst off, copy and paste this address into Windows Explorer: C:\Program Files (x86)\Steam\steamapps\common\Team Fortress 2\tf\custom (Or change it accordingly if you don't use C as a main drive nor do you use a 64 bit operating system, which would make it just Program Files.)
Next, download your mod from a site so you don't confuse yourself. Next, make a folder in the directory above to relate to said mod, like this:
http://i.imgur.com/ZqiOkX0.jpgNext, extract everything that would've been inside the tf folder to the newly created folder for that mod.
After that, you will need to open another Windows Explorer folder to C:\Program Files (x86)\Steam\steamapps\common\Team Fortress 2\bin and look for the program called vpk.exe, like this:
http://i.imgur.com/thYCde1.jpgDrag the mod folder onto vpk.exe and you'll see a newly created vpk file with the same name as the folder:
http://i.imgur.com/DFikV9M.jpgRun the game and see if it works! If done properly, it should install normally:
http://i.imgur.com/wEDWESb.jpgHope this guide clears everything up!