Few Issues...not sure where to start first?
 

Ok, I have an '04 manual trans. 51,000 miles.
Been having trouble with a rough idle, more so when clutch isn't pushed in.
Noticed lately while warming up my car in the mornings, it will be idling a little rough, then when I turn the heater on it gets a little worse, and when I turn on rear window defrost, dome light dims slightly, and idling gets even worse.
Sounds like it could be the mounts, from the fan/ac causing it to worsen. But the rear window defrost?? alternator failing? but would that cause the idle to worsen? Was set on changing plugs/coils/wires this weekend (monday/tuesday is my weekend, lovely air force) but since I noticed the dimming and idle change due to the defrost, don't know which direction to go in first?

is it cold where you are?

The coldest it's been so far was low 30's