That is the scenario officials at Earnhardt-Ganassi Racing are discussing, sources close to the situation told ESPN.com.
Almirola was slated to drive the No. 8 vacated by Mark Martin this season, but the company was having trouble finding sponsorship for the untested driver.
Labonte, who received his release from Petty Enterprises last month in order to pursue other opportunities, is expected to fill the seat that Dale Earnhardt Jr. made famous before he moved to Hendrick Motorsports.
The 2000 Sprint Cup champion, according to sources, has drawn interest from several sponsors. He was unavailable for comment.
Montoya drove the No. 42 during his first two years with Chip Ganassi Racing with Felix Sabates. But with that car only half sponsored by Wrigley's and the No. 41 fully funded by Target, officials are looking to make the switch for what had become the top driver at Ganassi.
Truex will remain in the No. 1 sponsored by Bass Pro shops as he was at Dale Earnhardt Inc. before the merger.
Almirola would drive the fourth car in next month's opener at Daytona International Speedway and a select number of other races unless officials find a way to fully sponsor that car for the season.
Officials from Earnhardt-Ganassi could not be reached for comment.
David Newton covers NASCAR for ESPN.com. He can be reached at firstname.lastname@example.org.