Yesterday I was given a PGP rotary sprinkler (4" pop-up) by my neighbor to replace one that was leaking between the turret and the body. My neighbor works for a lawn care company and does minor irrigation repair. The PGP he gave me is made so you can completely dis-assemble the thing. All the PGP's that were installed in my yard by an irrigation company 6 years ago, cannot be dis-assembled. Aren't all PGP's the same?