Original title to a 69 swinger 340 can I keep it?

I have recently purchased a all original 69 dart swinger 340. It still is titled to the original owner . Which is the first title that was given when new. I have all other original documents IE( window sticker , build sheet, manuals and warranty card ). Amazing to me. Unfortunately a victim of the Vietnam war. The wife kept the car until 2 years ago when a friend bought it from her because the garage it was in started to calapse. The title was signed off by her in 1989 and stamped by notary public. She gave the title to her deceased husbands brother so the son wouldn't get it. ( drug addict).the brother never signed it, it is still open. The miles on the car are 50k original. There is no odometer statement on the title. How do I maintain original miles?can I some how keep the original title? Please help. I live in Indiana. Thanks for any info. This is a great car. I just purchased this car from my friend.