Welcome Jim ,
a SIP 100 will be a bit underpowered for rangy stuff but with some careful prepwork you might just make do by running it flat out. Ideally you need something around 150A for landys and rangys due to the heavy chassis sections.
How many power settings does it have?
Will probably want a new wire liner too if it's second hand. Fortunately the mod Woz mentioned is linked from the bottom of the replacing a wire liner page.
Steel liners are much better than plastic ones for mild steel wire though.