Al Hinkle posted this link on Facebook (yes, the real Al Hinkle who was Ed Dunkel in On The Road - click here if you need a character guide for Jack Kerouac's novels). Al is one of the few compatriots of Jack still kicking, along with David Amram, and is the only one left from the road trips.
This article from Gothamist discusses Jack's wish that Marlon Brando play him in the film version of On The Road. It also has an image of the entire original letter.
I posted about this on June 14, 2011. My reason for reposting? It's pretty cool, and I wanted you all to know that you could find Al Hinkle on Facebook.
Thanks, Al, for being Jack's friend and thanks for keeping us in the beat loop on Facebook! Daily Beat readers - get thee over to Facebook and be Al's friend!