Ramses the Great's American tour is wowing 'em in Texas, where Dallas and Houston museum officials are trying to extend the 2 1/2-year-old tour of the legendary Egyptian monarch's personal effects so as to include their towns. "Ramses already has been so long in the United States, he's asking for a green card, permission to immigrate," joked Zahi Hawass, archeology adviser to Egypt's Culture Ministry, in announcing the Texas museums' wishes. Hawass said the ministry would study the proposals and reply soon. The popular exhibition contains 72 objects from the life and times of Pharaoh Ramses II, the ancient Egyptian warrior and builder who reigned about 3,200 years ago. It opened in Montreal in mid-1985 and has toured Canada and the United States since then.