You should install the rear drive shaft before you unhook. You will need to have the t case in neutral to line up the shaft with the rear yoke. Yes the parking brake can and should be used, maybe even a wheel chock. If still hooked to coach twice the safety.Im leaning towards just removing the rear shaft completely since I can with the SYE. And was figuring Id be able to unhook from the RV and park the Blazer by locking the hubs, putting it in 4hi and driving it in FWD like you said haha.