If your really crafty you can go to your local bone yard, fab up some brackets to mount a old smog pump and use the suction side as a low buck vacuum pump. Works good and I've seen many used like that especially at my hometown redneck track here in north missisppippi, I've always used the header evac set up for my cars and I've never had any problems with them personally and I dont see why you should be able to use just one side of the engine if one of your collectors is tied up with a ego sensor. I've also seen then use old blower motor fan motors as water pump drives, I'm just a little more picky about how my stuff looks but hey if it works use it. ><Cp