The battery that people seem to have used is the Odyssey PC 295, but on one of the moparts posts I was pointed at, someone said that the battery would not start his 440-6 when it was hot.
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I have the same set up of 6PKRTSE (PC 925 Odyssey)
Never had hot cranking problems a 451 cid 11.25 cr

SPECIFICATIONS
Pulse (5-second) Hot Cranking Amps (PHCA) 900
Cold Cranking Amps (CCA) 330
20Hr Nominal Capacity (Ah) 28
Reserve Capacity Minutes 52
Dimensions L x W x H (in) 6.64 x 7.05 x 5.04
Metric Dimensions L x W x H (mm) 168.6 x 179 x 128
Weight (lbs) 28
Weight (kg) 11.8