They are right at the WN&P depot in the center of town.
The cars were moved over from Derry where they were kept for a while on the M&L near Bensons hardware. When they arrived in Sandown they had already been painted red which was thought to be in homage to the B&M territory they were placed in. The Sandown team researched the cars and found them to be of MEC heritage and decided to color them in the later green scheme.
I think both colors may have been used on the MEC anyways though...
If you watch the 1940s-50s Mountain Division video by Heron Rail Video, I seem to remember seeing a similar MEC flanger in Bartlett wearing an oxide red color with white lettering and a matching "shorty" wedge plow ( 2 axle wooden plow).