[R-390] Re: {Collins} counter sunk holes R-390A

[DJED1@aol.com]

I noticed that picture, and I suspect that what has happened is that someone 
forgot (or lost) the countersunk lock washers that go in those holes.  
without the washer, the screw head will be below the surface of the panel.  I 
agonized over whether I needed to mailorder one washer from Fair after I lost 
one- but I found that a conventional washer would compress to the proper 
shape. 
'62 Amelco- all original
Ed