Darktitan

******Update****** Recently after making the above post... Tekkit Classic has now been updated to a brand new Tekkit, which now just so happens to contain Galacticraft!! This new version is now included in the most recent technic launcher and currently supports 1.5.x and later. Thanks to the Technic crew, all modders/creators of the mods included in Tekkit (and anyone else I failed to mention) for listening to us.... and a special thanks to micdoodle8 for revolutionizing the way we all play Tekkit ^^ Keep up the epic work guys!

It's most likely not possible to combine Tekkit "Classic" (MC v1.25 x) with Galacticraft (latest build using MC v1.5.x) as Galacticraft is too new... However, it is 100% possible to successfully combine Tekkit Lite with Galacticraft. I am currently playing around with a test server of mine that utilizes a mods from both modpacks with the server running MC v1.5.1 I even have the portal gun mod running with it all ^^ The only downside about running such a recent MC version is that Tekkit Lite actually does not "yet" (as of the date of this post) support 1.5.1 so you'll have either 1 of 2 options. Option1: Update to the latest version of Tekkit Lite, take note of the MC version it uses (1.4.7) At login screen, take note of the FML (Forge Mod Loader) build MCP build helps too.. With this information in mind head off to the Galaticraft forums and find the Option2: Find the mods manually here and make your own modpack, perhaps one based off of the latest galacticraft build (1.5.1), basing tekkit lite related mods around it. (google the mod name + 1.5.1 to find them if they're not listed on there). I must note that you may have issues with some of the mods after copying the entire mods folder over to your server, remove anything related to rei_minimap and try renaming the .jar extension on ThermalExpansion-x.x.x.x.jar to something else (or move it out of mods folder) until the other mods like IC2 load as when they generate their configuration files for the first time mods like IC2 conflict with Thermal Expansion. After the server has loaded the config files for the other mods, shut down the server and place/rename the ThermalExpansion-x.x.x.x.jar in the mods folder...restart....should have no issues. Galacticraft imo should be integrated with Tekkit as it's quite the revolutionary modpack.