You don't need to upgrade to the 30274 ejector unless you're experiencing ejection issues. The 336 ejector works fine, the 30274 ejector was designed to change ejection enough to fix another problem.
For Lodestone:
1. Get the 30274 ejector.
2. If the gun still ejects erratically with the new ejector, that means the extractor is out-of-spec and needs to be replaced. Keep the new ejector in the gun and replace the extractor.
3. Alternatively you could try a .40 LCI extractor, using a .40 extractor has solved the ejection issue for a lot of 9mm Glock owners.
To get the 30274 ejector, you can try to find a Glock Certified Armorer in your area who would order and install it for you. Or you can order a Gen4 9mm trigger housing which contains the 30274 ejector and install it yourself.
You could also call Glock, speak to the Warranty Service Department, and explain the issue to them. Tell them you'd like them to install the new ejector to fix the problem. They'll likely tell you to find a local Glock Armorer to order and install the parts for you. If you don't have an Armorer in your area who will do that for you, tell them that and ask that they send you a prepaid shipping label so you can send the gun to them and have them install the new parts. They may agree to give you a prepaid shipping label, or they may not, it just depends who you talk to. If they won't pay for shipping, you'd have to send the unloaded gun via Fedex or UPS overnight which can be pretty expensive.
Only two retailers have been confirmed to sell the Gen4 9mm trigger housing that has the 30274 ejector in it, and they're both backordered at the moment:
1.
http://www.midwayusa.com/product/225860/glock-trigger-housing-with-ejector-glock-9mm-generation-4
2.
http://glockparts.com/Detail.aspx?PROD=123022&CAT=748
Here are some detail strip resources if you need them, you'll need a 3/32 inch punch like the Glock Armorer's Tool:
Make sure when you reassemble the frame, that the locking block pin is in the frame
before you install the slide stop. This will ensure that the slide stop spring goes to its correct position, under the locking block pin, to give the slide stop spring its tension. If you install the locking block pin after installing the slide stop, you may damage the slide stop spring and the spring will not be in the correct position, resulting in the slide locking back with ammo still in the magazine.
On the following page are some Glock Armorer's Manuals, just scroll down to the "G" section. I learned from the Update Manual and 2009 Manual. The 2009 Manual has a few pages missing, but that info can be found in the Update Manual as well.
http://stevespages.com/page7b.htm
My new 17 has the 336 ejector and an 02 spring, calling Glock in the am to see if i need upgrades to it.
As long as the gun ejects fine, you don't need to upgrade to the new ejector. The latest guide rod assembly for the Gen4 G17 has 0-2-4 on the base of the guide rod, here's a chart showing the latest guide rod assembly for each Gen4 model:
http://www.kaneohegs.com/images/Glock_Gen4_recoil_spring_assembly_ID_chart.jpg
If you want to upgrade to the latest guide rod assembly version, Glock offers a free recoil spring exchange program, they'll send you the newest version and a prepaid return envelope to return the old version:
http://us.glock.com/customer-service/recoil-spring-exchange