there is one of those supercube amps on ebay right now for $150.
it likely has eq for the sealed supercube enclosure.
that eq is an unknown and will not be compatible with a ported enclosure.
the amplifier is also an oem, which means it was designed to work with some driver.
we do not know what the resistance of that driver was.
the amp may be compatible with your jl woofer, but without knowing, it is impossible to recommend.
hooking up a driver with too low of an impedance can burn out the amp.
audiophile, the reason he wants to use the supercube amp is that will match all his other deftech gear and because it appears to be a simple solution.
without knowing some details mentioned above, this build will be a crapshoot.
good luck, god speed, may the force be with you...i hope it all works as you hope.