Easy job, can be done on drive no problem, but a bit time consuming.
Old ones easy to cut or pull out, new poly ones easy to put in, use a block of wood to space the beam away from the body about 3", then use the long through bolt as a draw bolt to pull the new ones in, use plenty of grease in the cone shape on the beam as they need to compress a little going in, just apply some pressure and leave a min, then a little more you will see them go in slowly, massive difference they make.
tabetha