This mod adds some edited versions of the existing fuel tanks and engines to KSP with different things like more fuel, solid fuel rockets that can turn off, a fuel tank that has all the fuel in it, etc. I will upload an actual photo later but I'm a little short on time right now so just cool your jets (lol). Due to problems logging in, everything below V2.6 is under the username "TheDerpSquid1". Also, added in V2.6 is the SICT, a (hopefully) working cloaking device which can be downloaded on its own as well.
Other Downloads:
Github Download