Do you have access to a scale accurate down to single milligrams, properly calibrated? If you don't, I wouldn't even try this. Don't think I'd bang it either, IM seems more reasonable. Do you need to know how to prepare solutions for IM, how to go about needling yourself, and the like? I'm sure there are already threads for these things...
Are you experienced with at least ketamine or PCP analogues? I can't imagine going balls deep with dodgy cooked up street PCP without having tried some similar substances that have at least a lesser duration.
I remember reading this years ago, can't find F&B's first trip PCP trip report, the search hates me, but you could dig, or ask...
http://www.bluelight.org/vb/threads/330462-PCP-2nd-Time-Ketamine-s-Weird-Big-Brother