Last time I did the intermediate shaft oil seal, I just unbolted the seal carrier from the block. "Pressed" the old seal out with a pair of sockets and a vise, then pressed the new seal in with the same method.
You need one socket that's the same size as the seal (outer diameter) and one socket that's bigger than that, so you can press it out. To press it in you just need the smaller socket.
Remember to replace the carrier gasket, as well.