Hey, that is a great start. I see that you have modeled it in Milkshape. Lucky for you, there is an exporter available here:
http://chumbalum.swissquake.ch/files/MilkShape%20Plugins%20R4%20No%20Installer.zipSimply install those plugins, and go to the export menu and choose the SFC Mod exporter. Then, you have your model. You did not state which version of SFC you wanted to use it in, however there is a good tutorial for adding ships here:
http://starfleetcommand3.filefront.com/file/;40101If it is for SFC2 or OP then you can simply go into your main SFC directory, browse the folders and in assets/specs you will find a file called shiplist.txt. Open it up with excel or note pad. Each line is a different ship. Choose the ship that you want it to act most like, copy that line, and insert it. On that line change the file path name to where your ship is (most likely assets/models/thing/thing.mod). Change the ship designation for that line e.g. FCA to FCT. Save the file, close it, and go play it.
You will learn alot more if you do it yourself by trial and error. Once you have the mesh complete, it is probably the easiest modificaiton for a game you could ever do. Lots of fun for very little effort. Once you have attempted it a few times, and if you run into trouble, post here again with specific sysmptoms and a description of what you did. We will be very willing to help.