I have both thin-ish 60/40 rosin core solder, and a thicker one that has no label, but pretty sure it's rosin core (as I got it at Radio Shack) and probably 60/40.
Is that iron powerful enough to not fry a pot when getting wires grounded to it?
40-50w is enough and the melt point of solder is 370F. 450F is probably enough to heat the pot back with enough speed to melt the solder with no damage to internals.