Please do not take this as criticism or hating, but I think there may been some confusion here. Are you saying you or someone installed the 4.7 final drive?

Only the JDM '98 spec ITR trans came from the factory with a 4.7fd otherwise its a 4.4fd.

Also, every factory spec LSD trans that I have seen has "LSD" stamped on the outer housing.

Regardless, even if it is a USDM ITR trans, its still a very fair price.