Rather than deleting the Lower 48 map img, I renamed it on the 885.

But the unit said there were no maps installed even though I had the Full North America 2016.10 maps on the SD card.

I renamed the gmapprom.img to gmapsupp.img and the unit recognized the maps.

Just for kicks, I went back and restored the name of the img file on the unit to gmapprom.img, and the units still functions.

I don't know which map img file it's reading.

But this old 885t is running S-L-O-W. Slow to respond to touch and very slow to draw maps etc.