Actually the plan IS for a Garrett

Ed and Bob are in fact planning to build a garrett-type loco out of the two 490's, not a mallet. Bob has assured us he can do so with no permanent damage to the historic integrity of the 490's....at some future time the garrett could be disassembled and the two engines returned to service as 490's. One unresolved issue is the impact of the reduction in tractive effort that occurs as coal and water are consumed, thus weight on drivers is reduced. They are currently studying the profile of the new line to determine if that will be a problem. They think not because the higher tractive effort will probably be needed only early in the trip. The garrett will be used on Ed's new Pagosa branch, which will NOT follow the old branch from Pagosa Junction, but will take off from just west of Cresco and head northwest to Pagosa via a much more scenic route. Work on the garrett will begin soon after the 492 is returned to service, following the 483.