Did I figure something new out here? Somehow BaseCamp which isn't supposed to support my Summit HC let me transfer two sections of a free Texas Topo map to the 24mb internal
eTrex Summit
GARMIN 010-10314-00 CARRYING CASE FOR ETREX GPS RECEIVERS for sale online | eBay
eTrex Summit® HC | Garmin
Garmin Enduro GPS Watch In-Depth Review | DC Rainmaker