4l80e gurus question

Noticed a spot on drive other day , so pulled dually in garage and had a leak around the yoke coming out the back of transmission. I bought a new seal...my question is how hard is it to replace that seal. Must have just started in driveway, cause once on jackstands...there was no fluid slung underneath anywhere. Just a little around where the yoke goes in transmission. And truck has been setting on stands for a couple days, and noticed there is no more fluid leaking out now. Any input? The seal was like 5$ , so went ahead and bought it. Was just curious how hard it is to replace...?

not a guru but work on cars all day long just need to drop the drive shaft and use a seal puller or prybar then tap new seal in reinstall drive shaft