LEDs

Order of assembly and wiring steps (this is how I do it)

Paint everything one coat - Faux-Wood finish on the floors if chosen
Sand until the paint is thin and transparent and lots of wood is showing thru
Build the housebody up to the roof (No Dividers)
(J545 only) Paint the Housebody - 2nd coat
Attach the Front Roof - not the Rear Roof or Attic Partition
Lay the Main Loop of tapewire and leave 2" or so taped to the bottom of the base floor on both ends
Ceiling Loop in the first floor ceiling
Install the Divider and Attic Partition
Finish wiring the inside, testing between each step. I do a Sconce Loop in all rooms, connecting them on both ends ("Net" style)
Coach Lamp(s)
Attach the Foundation and Porch but not the Porch Roof
Ceiling lights in the Porch and outlets for seasonal decorations are most easily accommodated
   with outlets wired through the upper wall to the Base Loop in the Attic
Attach the Porch Roof
Finish the inside (wallpaper or wall liner paper and paint)
Attach the Rear Roof
Shingle
Touch-up the painting

If you've come here after some of the above steps have been bypassed, don't worry - among the resources on the wiring page are ways to proceed working around most anything (except too much interior finishing... Stairs, Baseboard and Crown molding, Doors and Windows, those things I take out if I am going to use tapewire)