This article, originally published at 8:14 a.m. on Friday, Nov. 13, has been updated with the final exchange ratio for GE's Synchrony share swap.

One of the biggest lessons General Electric (GE) - Get Report  learned from its three decades at 30 Rock, the Manhattan landmark that's home to NBC, came when CEO Jeff Immelt sold the media business two years ago.

The manufacturer's tax bill was huge.

Now, though, that costly lesson is paying off, to the tune of more than $1 billion. GE locked in the exchange ratio for its Synchrony Financial (SYF) - Get Report share swap on Thursday and plans to end the offer at midnight on Nov. 16, winding up a deal that that lets it shed an 85% stake in its former credit-card unit tax-free.

The transaction is one piece of CEO Jeffrey Immelt's plan to refocus the company on manufacturing operations from health-care equipment to jet engines and locomotives while exiting most of the lucrative GE Capital lending business. While profitable, the finance unit had dragged on GE's stock since the financial crisis and subjected the company to strict limits on how it invested capital.

Since Immelt announced his strategy in April, he has agreed to sell $126 billion of GE Capital's loan portfolio. The exchange with Synchrony, which went public last year and is valued at more than $20 billion, is one of the biggest steps in the process. It benefits investors because GE plans to retire the stock it gets back, spreading earnings over a smaller pool of shares and potentially driving up the price.

GE is offering 1.0505 shares of Synchrony, which closed at $30.79 on Thursday, for each share of GE that its own investors turn in through midnight on Nov. 16, the company said. At Thursday's closing price of $30.16 for GE, that would amount to a buyback of $20.2 billion.

"The result is good for GE shareholders as we expect to retire about 671 million shares and reduce our outstanding float by approximately 6.6%," GE Capital chief Keith Sherin said in the statement. 

The mammoth exchange is even larger than Pfizer's roughly $11 billion swap for animal-vaccine maker Zoetis.

Its tax-free status is a far cry from that of GE's $16.7 billion sale of its remaining 49% stake in NBC Universal to Comcast in 2013, which broke apart a two-year joint venture and came with a cash tax charge of $3.2 billion.

 GE, based in Fairfield, Conn., had taken control of NBC with the 1986 purchase of Radio Corp. of America for $6.4 billion, gaining offices at 30 Rockefeller Center in the process. Almost 20 years later, in 2004, GE purchased 80% of Universal Studios and group it in a unit with the broadcaster.

With Synchrony, in terms of applying capital gains tax alone, GE is saving at least $1.2 billion. That's based on a standard 20% rate applied to the $5.9 billion increase in GE's stake since the lender -- which GE started during the Great Depression to provide financing to appliance customers -- went public last summer.

The swap was first outlined as a "very tax-efficient transaction" by GE Capital chief Keith Sherin, who described it as the "last step, the biggest step, remaining in the transformation of the portfolio of GE Capital."

While the total gains on the transaction have yet to be determined, GE is expected to realize "significant value creation," according to William Blair analyst Nick Heymann.

"Additional positive announcements between now and the end of this year could allow the shares to reach $32 sooner, possibly by late this year or the time GE reports fourth-quarter 2015 earnings" in January, Heymann wrote in a report Thursday. "We also believe it is highly feasible that GE could double in price by the end of the decade to about $60 per share."

GE's stock was up less than 1%, at $30.17, in early afternoon trading on Friday.

Even more encouraging than Immelt's success in shrinking GE Capital has been the host of recent manufacturing orders, from a $16 billion engine-maintenance agreement Monday with Dubai's Emirates airline to a $2.6 billion deal to supply India with 1,000 diesel trains, Heymann said.

"GE is winning new industrial base infrastructure projects from a wide variety of developed, emerging, and non-developed countries at a time when sales of traditional industrial finished goods" aren't robust, according to the William Blair report.