Things get much trickier when soldering to terminal posts.You need a high wattage pencil for this preferably 60 watts chiesel type,or a soldering station that can go up to 1200 degree F.If you were soldering at any other location the wattage and temp. is not as critiical.If you need to apply a resistor to a terminal you really have a big risk for a cold solder joint because a terminal requires so much heat to form the solder properly.You have so much more metal to properly heat up.It's just something I've learned from my years of soldering.You need alot of wattage and heat at this particular location IMO.
Good Luck and be Patient and Careful.
Good Luck and be Patient and Careful.