I have an HO scale locomotive; item no. 50711, USRA 0-6-0 w/smoke and Vanderbilt tender - GN (purchased 10-15 years ago).  I have lost the schematic, but my most immediate problem is that the part that attaches the lokie to the tender (can't remember what it's called) is no longer attached to the tender and is missing its screw.  Can you help?  Thank you!