You'll have to pull the tailshaft housing, so once it's off you wont really be doing it in the car. After that you can split the bushing carefully with a chisel and press the new one in with a socket or PVC coupling. Or you can take the bushing and tailhousing to a shop and have them press the old out, and new in.
Been awhile since I did one, but it's a pretty fast job if memory serves me. Takes longer to R&R the tailhousing.
The only way I have ever seen it done is the way 1946Austin has described. I'd like to see this tool and the procedure for using it. Seems to me you'd be working blind, but if it simplifies the R&R that would be a home run.