Using a resistor to simulate a voice coil

I have on Infinity Reference 1242w 12" sub.  It is a dual 4 ohm model.  However, my box is built for 2 subs and I have yet to order the other sub.  Crutchfield has a 2 for one special on the 1240w, which is a single 4 ohm version.  I want to order the 2 1240w's.

However, my amp is makes 600watts rms @4 ohms, and that would make the subs see 300 watts a piece, if the amps sees a 4 ohm load.  Can I use a 4 ohm resistor in series with each woofer, and then parellell the woofers together to make a 4 ohm load?  Why or why not.

Good point, I'll probably look around to see if I can find some. 

However, my amp is a 2-channel, producing 200 wattsx2 at 4-ohm.  If I go from 300 to 200 watts, i will have about a 1-2db drop right.  Do you think I would ever notice the difference (especially $100 difference)

Thanks for the help

Jacob