At the funeral Mass at the film's end, the congregation's response to the priest's opening liturgical greeting "The Lord be with You" is .."and with your spirit". This is a well known change made recently. The funeral takes place in 1987 where the liturgical response would still have been, "And also with you."
At Liberace's funeral the Catholic priest says "the Lord be with you" and the congregation answers "and with your spirit." In 1987, the year Liberace died, the response was "and also with you." It didn't change to "and with your spirit" until about 20 years later.