If we want to practice ihtiyat when it comes to taqleed, do we have to take into account the rulings of all the living maraja or all the living AND dead maraja?

Ihtiyat in taqlid can be practiced by one who has studied jurisprudence and is able to understand each ruling and the number of opinions in regards to it, the sources of these opinions meaning how the marja has reached that opinion. Therefore the person should be one who is a mujtahid and then the person would chose the hardest amongst all the opinions. It is not a case of looking at the book of laws of a few maraje and choosing one to follow.