One for Dave or maybe Ed

[VonRyan]

Those are probably 3M Scotchlite Keystones designed to survive thermonuclear warfare.  The PRR used them on a variety of equipment in the final decade.

We WILL survive. 

[Robbman]

Yep.  That's why the PRR was called "The Standard Railroad of the World".

I know... thus the 'we make our own standards' joke there   At least they new well enough to borrow superior designs from the N&W, and to leave them them alone and just reap dividends

[Dave V]

Here's a great starting point...an unnumbered Pennsy SD-35 from Atlas.

http://www.ebay.com/itm/PRR-Pennsylvania-SD-35-No-Rd-manu-49423-Decoder-Ready-/171160705132?pt=Model_RR_Trains&hash=item27d9f9186c

Note the two Scotchlight keystones on the side...!

[nkalanaga]

Dave:  Sure enough.  Like I said, odd by Northwest standards, but then, the East has always seemed a little odd to me, ever since moving back here.