Not on a Ranger, but similar since the suspension is very close... the smart rule of thumb for Subarus is that once the boot is torn, replace the whole axle assembly. It's cheaper to buy a new axle with fully sealed, one piece boots than it is to f*ck around with split boots or having an axle shop rebuild yours with new CV joints.
Once the boots are torn, the grease leaks out and dirt gets in. It's generally a fair assessment that if the boot has failed from use and not direct damage (cut, etc), the CV is not far behind anyways. Even if you use a split boot and pack it with grease, the contamination is already done, and it's only a matter of time until it fails. Do you want to deal with a broken/failed axle while out in the wilderness?