How to replace a drive belt on a John Deere LX 255?

I have a John Deere LX255 Mower with broken belt. I have purchased an 88" belt which I believe is the correct length. I have it over the transmission pulley, through the idler pulleys and around the steering drive. I am having difficulty getting it past the mower drive pulley, the mower deck clutch and onto the drive pulley. Does the deck drive pulley and clutch have to come off?

Lantz Pohlman
July 2010