Precision Placement of Replicated Group to a target on a different layer

Find center of pin 1 on the target layer
  Board Geometry / Assembly Notes / Find: Lines
  Hover mouse over pin 1, rt clk Show Element Ctr x-y
    EG: -tttt tttt
  
Placement Edit Mode
  
Move Group

  Package Geometry / Modules
  Find: Pins ( only )
  Show element pin 1 of group 
    EG: x -pppp pppp

  Move
  Find: Groups ( only )
  User Pick
  Type in x -pppp pppp
  
  
  Pick new location for the element(s):
  Type in x -tttt tttt