Try this
require 'sketchup.rb'
def cpointseqxy()
model=Sketchup.active_model
ents=model.active_entities
layers=model.layers
tlayer=layers.add("cpointseqxy")
sel=model.selection
sela=sel.to_a
sel.clear
vec=[10,10,10] ### change these values for arrow length
model.start_operation("cpointseqxy")
cs=[]
ca=[]
sela.each{|e|
cs<< e if e.class==Sketchup;;ConstructionPoint
ca<< e if e.class==Sketchup;;ConstructionPoint
}
th=[]
ch=[]
lh=[]
ca.each{|c|
cx=[]
cs.each{|e|
next if c.to_s == e.to_s
if c.position.x == e.position.x and c.position.y == e.position.y
cx<< e
ch<< e
t=ents.add_text(" =XY",e.position,vec)
th<< t
l=ents.add_cline(c.position,e.position)
lh<< l
end#if
}
cs=cs-cx
}
th.each{|t|t.layer=tlayer}
lh.each{|l|l.layer=tlayer}
sel.add(th+ch+lh)
model.commit_operation
end
This has arrows for the text: vec=[10,10,10] sets the arrows 'vector', adjust the value of it to change the leader location, length etc...