heavens door can change atributes of a person like as if they are a book the question is theoretically could heaven's door alter or upgrade a stand's abillity? or is it limited to things that are physically possible. i think he cant upgrade stands or anything like that cause then to find kira all he would have to is give one of the morioh gang(probably koichi) some abillity to let them find kira instantly so it is probably bogged down to what is possible and can not do the impossible.
No, because Heaven's Door only alters memories, and not the physical abilities of the people themselves. You could have them forget an ability, but they cannot add or erase abilities.
Ex. Jotaro just vibing with Star Platinum the World. Rohan gets him and opens up his face. He takes a page from the DIO fight and leaves. Jotaro now no longer remembers he can stop time, but he can still stop time.