Stan, Dudley. Thank you most kindly. As of now, the only parts I am missing are the trip spring and trip pin, and the trigger lock (T shaped). If you have these, it will save me an afternoon. Feel free to send me a PM.
As a last resort, I've already cut a piece of an old worn out hacksaw blade to use as a trip spring. Hopefully its spring-steel is thick enough. I've got a drawer of old pin punches and broken drill bits to make a trip pin out of, and like I said I don't think the T shaped trigger lock would be too difficult to make once I know how it functions in each of the 3 positions of the safety switch.
It is more or less clear to me now in the design that the safety bar MUST be adjusted anytime the top lever is adjusted. To get a worn top lever back to center, the bolt guide block moves further to the rear. This requires the forward contact points of the safety lever (the part that goes through the receiver as well as the backside of the vertical part that connects to the T-bar) to be reduced. The point can be stoned down, and the t-bar connection can be gently bent further to the rear. I think I'm off by about 1/16", plus whetever the thickness is of the t-bar between the safety bar slot and the back of the receiver. This will all make better sense with more pictures. I'll get some.
Comparing pictures in alcaviglia's posts and album of a lewis, I am fairly confident I have the right safety bar. I am a bit confused be the long skinny groove along the underside of the tang. It seems the safety bar should ride in it...but it does not and I don't think it can, unless there is a bend in the bar that I don't have. alcaviglia's lewis pictures show the same. This could be easily adjusted as the safety bar is easily malleable - it's not hardened spring steel.
Pictures of a functioning safety in each of the 3 positions would be most welcome. I'll wait to form my safety bar until I see them.
EDIT: This is precisely the safety assembly I have.
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