I've had a lot of sleep paralysis run-ins in the past. It is definitely possible to achieve WILD through SP, just much harder if SP freaks you out. See, if you are afraid during the process, you can invite other beings into this dream state. Whenever I have SP, my eyes are barely open and I can see my room. It's believed that this view is actually a dream room. So, if you're in paralysis and you can barely open your eyes to see your room, you are actually dreaming, but you think you're in your real room sleeping. Because of this, you think you can't move when in reality you're in your dream room, in which you can move. The goal is to unlock yourself from your bed. The main technique I like to do is imagine I'm floating up like I'm being levitated out of my bed. If that doesn't work, I do the opposite and imagine I'm sinking into my bed. If you can master this, you won't have trouble imagining a dream scene because you'll already have one which is your dream room.