(Corrects 13th paragraph to remove reference to dollar index move on Tuesday)
* MSCI Asia ex-Japan slightly lower in early trading
* Japan's Nikkei opens down but erases early losses
* Bright spots seen in Japan economic data
* Dollar index gains, moves away from five-week low
By Lisa Twaronite
TOKYO, July 30 (Reuters) - Stocks wobbled and the dollar index edged up from a five-week low on Tuesday as investors positioned for the Federal Reserve's monetary policy meeting at which it might offer clues to the timing of its stimulus reduction.
MSCI's broadest index of Asia-Pacific shares outside Japan and Tokyo's Nikkei share average both opened slightly lower, although a weaker yen helped Japanese shares push into positive territory, and a spate of Japanese economic data contained some bright spots.
Central banks take centre stage this week as investors wait to see whether Fed officials would lay the groundwork for paring the Fed's $85 billion-a-month bond purchase programme as early as September. The Bank of England and the European Central Bank also hold policy meetings this week.
The U.S. payrolls report on Friday is also in focus, as an improving labour market would help determine the timing of Fed stimulus reduction. The report is expected to show 185,000 jobs were added in July, and a dip in the jobless rate to 7.5 percent. An upbeat report would lend credence to speculation the Fed will start tapering its stimulus in September, and would likely give the dollar a lift.
"We've been seeing very subdued activity from clients, as it's quite obvious people are waiting to see what comes out of the U.S. for further direction," said Bart Wakabayashi, head of forex at State Street Global Markets in Tokyo.
"There's a bit of a consensus that the recent sell-off in dollar/yen and equity markets seems like a prelude to some kind of dovish remark from the FOMC, and we'll be right back where we were three days ago," he said.
"It seems like we're setting ourselves up for one of those, 'buy the rumour, sell the fact,' type things, which markets and humans tend to do," Wakabayashi added.
Data released early on Tuesday showed Japanese industrial output fell 3.3 percent in June from the previous month, down for the first time in five months, but analysts see factory activity on track for a recovery backed by exports and private consumption.
Japan's jobless rate hit its lowest level in four and a half years in June and the availability of jobs hit the highest in five years, boding well for the government's efforts to revive the economy and end deflation.
On Wall Street on Monday, all three major indexes moved lower. European shares finished the day mostly flat, as weaker bank shares offset the boost to sentiment from two large mergers in the media and pharmaceuticals sectors.
Even with Monday's losses, the Standard & Poor's 500 Index is set to post its best monthly performance since October 2011, while Nasdaq Composite Index is having its best month in a year and a half.
Against the yen, the dollar gained 0.2 percent to 98.16 yen , moving away from its nearly one-month low of 97.61 yen touched on Monday.
The euro was little changed against the greenback at $1.3259 , while the dollar index added 0.1 percent to 81.741, moving away from a five-week low of 81.499 hit on Monday.
Commodities were under pressure ahead of the Fed meeting, and also faced concerns that manufacturing surveys later this week might highlight weakness in China.
Copper fell about 0.1 percent to $6,869 a tonne, while U.S. crude lost 0.3 percent to $104.27 a barrel.
Spot gold edged up 0.05 percent to $1,327.61 an ounce. (Editing by Eric Meijer)