So based on how Sanjay Rath defines, a Graha is something that causes Grahana. Or in other words, they eclipse (Not in a necessarily negative way) the houses they sit on and force the Jataka to do karma of certain types. The horoscope, as a whole, is essentially the celestial map of Prarabdha. The Grahas positions in anyone's chart describes what karma a person ought to do in this life.
My question is, "Is it possible to influence these Grahas by the virtue of their house position or sign position, willingly in natal or divisional charts?" In simple words, can a siddha reposition the Grahas in his own or someone else's horoscope? If yes, then what is the method he needs to follow?