I installed two of these:
NPP HR12390W FR 12V 390W, 12V 120Ah,12Volt 120Amp High Rate Rechargeable Sealed Lead Acid AGM UPS Battery
in a battery compartment with exactly the same dimensions as yours (Thor Compass 24TX). $420 for the pair from Amazon, free shipping. It's a tight fit, but can be done with just the right technique. They have been great.
__________________
|