Yes Terry, that's how it was done.
And you were the dream client for the project providing books, photos, parts, time and money to make it possible. Also the impossible to find, single-screw tang sight!
How many factory options did we replicate?
The difference with the '73 tang was that lever catch & spring, and of course, yours was a set-trigger tang with extra holes, etc.
There is a piece on making a lever action forend from scratch on my website.