The attachment doesn't appear to address the rear seal. Army's post on his troubles with the front seal is a good reference: http://www.peachparts.com/shopforum/showthread.php?t=278649&highlight=clamp

Getting the correct seal(s) for the correct model of pump is important. You'll need to ID you pump model. I'd call Phil and have him get you the parts for your specific pump.

Finding and accessing the 4 bolts that hold and adjust the pump may be easier by looking at the R-4 compressor thread I've posted. It shows the bolts and the pump removed.