Mounting an entity to a prop

I have a question.I am learning lua and trying to mount an entity to a prop once they touch each other.The entiry also has to be mounted at specific position so if anybody could guide me the right way would be much appreciated.Thanks

the right path would be
[lua]
function ENT:Touch( hitEnt )
if ( hitEnt:IsValid() and hitEnt:GetClass() == “ent_whatever”) then
hitEnt:SetPos(self.Entity:GetPos() + Vector( whatever , offsets you , want here))
hitEnt:SetParent(self.Entity)
end
end
[/lua]