The maaseh was, someone asked R� Chaim Volozhiner if the Gaon was as big as the Rambam. R� Chaim Volozhiner replied, �ulai keRamban.� The velt was amazed that R� Chaim Volozhiner was able to differentiate between the Rambam and the Ramban…
When the Poiskim are counting for roiv deiois in a machloikes Roishoinim, they count the Gaon as one of the Roishonim.
I wondered, if the would count the Shaagas Aryeh in that too.
My friend, Hagaon R� Avi Ort shlit�a heard directly from Maran R� Moishe who said, �ven mir iz gevezzen yung, mir flegt kuken oif der Rebbe Akiva Eiger azoivi mir hoben gekukt oif der Gaon.
Rebbe Akiva Eiger is also considered by many poiskim like the daas of a Roishon.
I have never heard on the Gaon the phrase the neshamah of a Roishon, just (and more to his credit,) he reached the level of Roishonim.