I’m not 100% sure of course, since it was an “orphan” I bought from gun choker or flea Bay; but all the features of the slide lead me to believe it is 2nd Generation, so I had at least a fair chance of it mating up with the 639 to at least an acceptable degree. For a while I considered going with a Gen 3 slide to get the heavier nose with dovetail cut for the front sight , but decided that qualified as “diminishing returns” and since this slide was already here I used it. I still may look into installing an adjustable rear sight from a Model 52 (that I still have stashed from yet another project) but I want to see how the gun works with all of the mix of parts it has now.

I see what you mean about the addition of the firing pin safety adding to the complexity of the 2nd and 3rd Gen pistols, but I guess that’s just the price I have to pay to get the stainless frame I want... there were no stainless examples of the 39-2, AFAIK. I’ll have to live with the extra levers and get used to fiddling with them when assembling and disassembling the gun. I’m relieved that when I shot the 639 donor gun and the old 39-2 side by side, the extra pieces moving around inside the 639 was not all that noticeable.

The project continues... stay tuned!

Froggie