My suggestion would be an Odyssey battery (model 925 will fit with lotsa room left over) and rather than an inverter, I'd suggest the Sure Power 1315 Separator. I've got this set up and it works great. There are instructions with the 1315 that will allow you to wire it to use the aux. bat. for starting when/if the main is to low. By the way, all the instructions about how to install and wire the system come with the 1315, it just that the "starter" option is an alternative, not necessary in order to install and use the 1315.
 
Bob Stevens
'87 Syncro Westy> > Hi All,> > I plan to install an Optima gel Battery under the driver's seat in my 85> Westy so I can use an Inverter for AC power..> Ive read some of the write-ups on how to do this, but can't find the model> number that was used.> Does anyone know the model number, and also where one can buy such a battery> in Canada?> Also, what might be the second best battery awailable that will fit under> the front seat?> > Thanks a bunch> > Alfred> 85 Westy
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