[1974ChevyC10]

i have a two piece driveshaft on my truck with the carrier bearing setup.earlier today i was fixing something on my truck and i rested my hand on the part of the driveshaft just after the carrier bearing and it shifted to the right and when i let go of it then it shifted to the left.visually the carrier bearing looks like it needs replaced.is there a certain amount of free play that is allowed in there carrier bearings.if it is bad will it fall out if i drive it.i do notice when i shift into reverse not only can i feel the shift into reverse but i feel a second firm "shift"-could that possibly be the carrier bearing shifting when i go into reverse.it doesnt do it when shifting into drive or neutral only reverse.im going to be moving to phoenix and will be driving my truck so i need to know if its ok to drive to phoenix then fix or do it before hand-i dont have the means of fixing it here but i do in phoenix.help me out here guys-especially ones with two piece driveshafts who may have went through this.