I really don't think you have anything to be worried about. These are OEM pulleys on my 440. Yeah, they're close together. Been running them for years - no issues. I had them powder coated before actually putting them into service. No slippage, no squeals. In fact, the powder coat has not worn out of the grooves. I can tell you that if your PS belt flaps at all it may contact the WP pulley and mar the finish.