auburn pro/31 spline axles

I just got an auburn pro diff and moser 31 spline axles. can i use new stock axle bearings and also can i re use my c-clips? I am really eager to put this in. one more thing, i read in another thread that it is possible to have a vacuum leak if the iac isn;t workin properly, mine is new and wont work, car idles perfect, i have adjusted the throttle plate screw and it still wont work (iac), so how can i find out if i have a vacuum leak? i have the trick flow street heat upper and lower, edelbrock 65 mm t-body, it ahs done it since then. I have tried the carb cleaner around the gasket area, no problems at all. any ideas are greatly appreciated. thanks

nick

one more...where can i get the ramcharger electric cooling fan???

i have my timing set at 14 degrees, the car runs good, but it just doesnt use the iac. If i unplug it nothin happens. I have tried the whole throttle plate screw, backing it out all the way and all, nothin works. so i have just left it for now. Like i said the car runs pretty good, it just bothers me and i am very picky about stuff. thanks

nick