I have a 1987 300E and i just found out that my ABS conrtol unit went out. So i need to know if it is possible to replace one myself and if it would require and any special tools, so far i know they range for a used one about $350-$500 and a new one $1000. So im going for a used one. Oh yeah are there any special instructions i need or anything to watch out for?

Thank You