weapons and engines are already out the as eye candy.
Non-functioning Engine Parts by Kaesar, is here. but not upgraded for the mods folder in 1.2.
Weapons Mod by me, is here.
my download is not upgraded for the mods folder (it will be reposted soon), but i have made both usable in the mods folder on my system and do use both when i build ships.
i didn't bother doing the defenses as i don't really use much defenses. i bring the fight to them