T-Man,
Glad to see you're gearing up for your 259E revival. As far as weights for the 259 go ...
My understanding (via earlier discussions with B&M) is that EARLY 259's had a weight in the steamchest (ONLY), and that later 259's (like mine) had two weights: one in the steamchest, and an "add on" weight inset into the floor of the cab.
Check out my 259E thread ... you'll see several photos that show the weights:
http://www.modeltrainforum.com/showthread.php?t=3748
The weight that is WEDGED shape is the one that gets mounted on the inside floor of the cab. The half-round "bump up" faces up, and the screw that holds the weight in place is the very same screw that holds the rear motor flange to the loco frame.
The steamchest weight slips inside the steamchest from the back (open) face. It was originally held in place by a rivet (axis running fore-and-aft), but I drilled this out for the repaint, and replaced it with a stainless screw and locknut.
The forward weight is nearly symmetrical top-to-bottom, but one edge has a bit of a recess to it. I forget if this recess faces up or down, but I'll try to remember to look on my loco to see.
A pic of the weights is below, but you might see more from other pics on my thread.
Do you still need front and/or rear trucks for your 259? I see them occasionally on ebay.
Cheers,
TJ
More clarification ...
The forward weight has two parallel protrusions (T's, really) that face aft. Here you're looking at the aft (rear) face of the weight. As I said, I forget if that subtle recess along the edge faces up or down.
Here's a better shot of the rear weight showing its wedge shape: