shaved tailgate

I have been interested in shaving the tailgate on my 2001 s-10. I've talked with a couple of different people that have this done and the have already had the seam crack. I know one of them had been told to brace that section but it still cracked within a month. Any suggestion what to do to keep this from happening?

make good welds, take your time, minimal filler, primer, paint. don't cool or heat it too fast either.