2400 lbs with the Motor . . . and mine is two door
It can be done 
The M5x/S5x and 302 are really close in weight.
There are a few known examples out there weighing in at 2230lbs (4 door + M52). One example I know of still had metal doors, albeit gutted and stripped. There are examples have CF doors, hood, and trunk (read: expensive!!!) what fall in this range as well.
As a point of reference, my car has 150lbs of power-heated seats. Also, don't forget nearly 120lbs of sunroof and mechanisms up top. Removing those items alone will bring the weight down quickly; as well as no stereo and speakers, no A/C, no back seat, no door panels, etc.
The weight of my E36 was ~3100. 270lbs of luxo equip (seats and sunroof), 60lbs of stereo, 30lbs of paneling, 60lbs of carpeting, 40lbs of wiring, 15lbs of center console (cup holders, armrest, ashtrays), 50lbs of back seat, 75lbs of AC, 50lbs of tar mat (sound deadening crap) . . . puts me right at ~2450lbs. I still have all glass windows, window regulators, and some wiring to sort through. I'm doing lexan for the sunroof panel and rear glass (15lbs). The racing seats and brackets will add about ~50 lbs.
It's the last 200-300lbs that is hard to remove on the cheap.
