I used one years ago on a 53 Sedan. It was like a "chinese" finger trap on one end and a cable with handle. Push the one end around the slot for seal after removing old seal, hook in seal and pull it thru, Yeah sure! I had to pull hard, practically hanging on it, and still had to turn engine over with scewdriver on flywheel to get it around. I even had the mains loose and pulled down some on crank, wich won't move much with trans still on. Sounds like the "kit" in last post has all the goodies to do the job.
I've heard also that new seals don't do good work w/out asbestos in them. Inliners site supposed to have someone with NOS seals for sale.