Have you ever heard of the BQ23-7 diesel?  It's not the same as the B23-7.  I got two of these Bachmann items in the 1980's and their motors are needing tune ups.  I had wanted to find the coboose that came with the combo set for it but I can't locate it.  The caboose was a tan off-center cupola with black lettering for Seaboard Coastline/ L&N.   I found an Athearn wide vision caboose with the same paint job as the locomotive though  and use that for it's matching caboose and it does match.  But none the less, I need to get these two locomotives repaired and tuned up.  What are the suggestions for doing this?