are you sure you got the correct size and group of battery? also might want to check other electrical things like ballast resistor, voltage regulator, and even starter realy. look for any frayed or worn out wiring in the engine bay or on the frame, sometimes even an unimportant looking wire can prevent start or drain the battery.
another thing i thought of, is you should check the bulkhead connector. when my truck wouldn't start it ended up being the negative and positive wires running thorugh the bulkhead connector to the alt. gauge. a simple bypass, and the truck fired right up. gatta love those dodges.
Let's start slow. If you mean you have no power (no lights, no nothing) then you likely have the infamous ampmeter problem. Before I bypassed my ampmeter and installed a voltmeter, the wires on the back of the ampmeter (the primary wires) would come loose (the nuts would back off), the connection would be no good, and I would have "no power". Also, if your ampmeter has been "smoked" the same thing will happen. Is this the problem you are having?
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