Been a while since I've done mine, it came to me disassembled.  The hammer difficulty is figuring out how the spring works.  It acts on the inside of the hole drilled in the hammer.  Not intuitive at all, as I recall, it puzzled me for quite some time.

I may have made a slave pin to hold the spring in place with the hammer, I can't recall.  That's an approach I take often, make it to hold everything in place, and when you put in the screw, it pushes the slave pin out, displacing it as it goes in.

Hammer needs to be all the way forward and resting on the bottom of the chamber. Once you have the two spring legs resting on their shelves. You should then be able to use a curved pick to bring the spring hole back forward into its proper position to insert the screw, Take your time and don't get frustrated its still challenging for me to do as well. Its also a bit easier if you lay the action on its side than trying to do it when its standing upright. There won't be any spring tension or very little if any then until you cock the hammer back and I hope this somehow helps you out.

I have a model J (if memory serves) that needs an extractor.  Would you be willing to send me a picture of yours so I can make one?

Thanks for your consideration, 
Tom

I want to thank all of you who answered my call for help. I just talked to Jerry H. and he got me on track. Now i will carefully read all of your posts and see if I can get the hammer back in. My wife just announced she wants to eat out so I will pick this back up in a couple of hours.

Eureka, I got it done, thanks to all you guy's help. Dave, the idea of a short slave pin is great. I can see how that would make the job so much easier. I will put the gun together tomorrow and post some photos. Thanks again. 

Thanks for sharing and happy to hear that you got it all back together just fine.

We are having our annual 3 day ISSA Regional event the first Friday, Saturday and Sunday in May if you are interested email me at johnnymlouis@gmail.com and I can forward you the sign up sheet and the list of events. You will meet and shoot with a great and helpful group of guys if you can make it out this way. Camping is also available and I can explain the rest in an email if you can make it to the event.