I made up a system that makes it easier. but definately not as nice as a tool.
30-06 casing with the casing filed near the base to create a flat spot for the extractor to pass by without touching.
2x4 with hole drilled to shove casing into and hold it firmly.
Small piece of metal very close to the hole size of the extractor hole through bolt.
Jam casing into 2x4 and brace on something. I brace it on the stairs.
Place the ejector and spring into the bolt.
Press bolt face into casing, compressing ejector.
Place small piece of metal into the hole on the thru side of the bolt where the extractor will be able to push it out in later step but also in the notch in the ejector to hold it, the point here is to hold the ejector tension and keep the ejector set.
place extractor and detent set spring and firing pin into bolt.
Press bolt into the casing to compress ejector again and snap extractor into place displacing small piece of metal placed in there to hold ejector in place ealier. ( you may need to use a small screwdriver to depress the extractor set spring before you can push it into place instead of just leaning the spring over.
Done. Say 'That was so much easier than the first time i tried putting that stupid bolt together'