The Engle portable system! They use 2.4 Ah when running! Very good on the power system.

Remove the old stuff (ONLY if you can't upgrade for a low cost) and just build a shelf to hold the portable! Much easier now and later!

See a couple of my notes in the below Solar panel thread;
http://cruising.sailboatowners.com/csbb/index.cgi/page/1/md/read/id/184723/sbj/it-s-a-system/

Greg