LordBlade already mentioned this, but he didn't emphasize it enough. If you care about D-Mods and not having them, the Hull Restoration skill is absolutely imperative. The chance of removing a D-Mod is not 100% but it's pretty high. Until the very endgame, when millions of credits mean nothing to you, don't pay millions of credits to remove all the D-Mods off a scavenged Legion XIV when you could just have Hull Restoration and probably have them all removed by the time you get your new ship back to your base to equip it.