If you take your time, you can do it. Read up on the subject first. I have never spot welded, but I have played around with a mig. The mig is farily easy to master, but you want to play around on some scrap metal until your proficient.

The thing is that we amaturers will probally take 5 to 10 hours to do the same amount of work as a professional body man can do in an hour.