if you disconnect the remote wire that raises the antenna it will just go back down because it is just a signal wire that tells it to go up or down. you would have to disconnect the power from the antenna when in the up position to make it up all the time. (you could just disconnect the harness in the trunk) Also if you hook your amp up to the power antenna make sure that the power antenna is always up (not just up when the radio is on but also cd mode) because if you dont your amp will turn off when you listen to anything else other than the radio. It would be easy to tap off of the ACC wire on the wire harness on the back of your headunit which is usually the red wire (you can test with a voltmeter. it should turn on and off with the ignition.
1994 SSE, 180 t-stat, gucci accented interior, suede headliner, eclipse avx5000 headunit, two 7.8" sunvisor screens, two 7" headrest screens, dvd player / tv tuner, infinity kappa perfect 5.1 components, infinity 12.1 perfect in the trunk, 2 rockford fosgate 350s powers, infinity refrence 7541a, 0 gauge audiobahn high flow wiring, duralast gold battery, sound dampened trunk and doors, xenon-white headlights, 2 15" and 1 20" red neons shine on the back doors, 2 3" and 6 12" blacklights lighting up the whole interior, red leds in the vents, red optx el neon pedals, red streetglow headlight leds, clear corners, pilot seven color angel eyes, blaze seven color underlighting kit, viper 791 xv.