Well here it is. . all done and it works great!! Used Red Oak wood and Golden Oak stain. 4 days of work, lots of sanding. . a few mistakes but it looks good and is functional. .
there is expano foam insulation under and around the bin, used a clear food storage bin from wal-mart and then painted the outside of it white. . the box is mounted right on the seat mounts and I had to recess the arms of the armrest to mount to the box. . that is how my last one was. . The rear open bay is a catch all for cel phones or whatever. . my armrest box is full!! lol. .
The cooler bin is 10" long x 8"wide x 7" deep. . Enough for a 6 or 8 sodas or whatever. . even long enough for a 20 ounce bottle sideways. .
Don't know if I want to do another one. . had to use the armrest for fitment several times...
The overall dimensions are ... 19" long, 14" wide, 8" high plus the lid 3/4".
I did this box style and the bolt dimensions for mounting is 10 1/4" exact x 14" exact. The bolts for the box, since the front and rear were not to be accessed to tighten, I... JB-Weld the bolts in place. then I could do the insulation and I did a false floor for the rear bay. . used some small blocks to raise a couple of panels of wood above the bolts for the lower box. . still see bolts for armrest but that is OK. . . . there is a separator wall behind the cooler for the junk bay. .
I'm no wood-wright but it looks good. . take my design cues if you want to tackle this... The front nuts under the seat is easiest to get to from between the seats with a ratcheting box-end. . the rear nuts are easier.