i'm in the same situation. sort of. it's not like don't have reverse at all... reverse is there. if i gas it right as i'm shifting into reverse i get reverse. if i shift into reverse, check back to make sure im not going to run anyone over, hesitate...etc...etc, then i have no reverse. also, when that happens and i floor it i can get it to move backwards but it goes super slow. all other gears work perfect.
i have yet to try removing the linkage and see if i can get reverse that way. when i had the pan off for a fluid/filter change the other day i noticed nothing out of the ordinary. fluid was nasty and burnt smelling but there weren't any pieces of metal or flakes or chunk that shouldn't be there. i haven't had the vehicle very long, i was told by the person i bought it from that the trans has 30Kmiles on a rebuild.
i'm going to try the adjusting the linkage but does anyone have any other ideas off the top of their heads?