Yup, Thats about all there is too it. I bought some miller female lead plug-ins to use regular miller leads from an old buzz box I had. Mine was an old Ford alternator. Friend of mine used to work at a local repair shop. He checked out the bearings and said it is putting out around 60 amps. or whatever. I run fairly small rod nad have only used it once. But it is the one time that it pays off. A friend broke his tie rod and we got him back in action for the whole day. I think he drove it for a month after the trip!
I used a combination pulley on my YJ to run a separate v-belt that I only use when I want to run the welder. The pulley cost a few coins.
The funny thing with mine is I gave my old welder (and the leads) away and built another set of leads from scratch. got more into them than the whole setup!
Here's a pic if I can get it to load. It's kind of hard to see. I ran a hot wire on from the battery to the field with a toggle in line. I think I read somewhere that they put out whatever volts are input at the field. Some evidently use a dimmer switch froma lamp or something to get some adjustability. I figures I would just change electrode size like you would if you were using a bunch of batteries in series. 3/32 6011 farmer rod worked perfect. maybe a touch hot but I prefer it that way. It's a real wild sounding weld too. I was pleasantly surprized it worked so well.