It helps avoid shorts if you place stripped off wire insulation on the bare cap leads. "Spaghetti" they call it. You can make your own from scrap wire of large enough gauge (old house wire or power cord) or even use coffee stirrers (very small straws).
The "dim bulb"
For a quick substitute for a variac, wire up two outlets in series. One outlet plug in a lamp that has say a 100W light bulb, and the other plug is for the TV under repair.