do it urself. it's so easy. i put the place racing mounts in my car on last sunday. if u got car ramps, use them. if not, just get the car up on jack stands. put a floor jack with a wood block under the oil pan to support the engine. take out the front and rear motor mount thru bolt. take out the center member (the piece of metal the mounts are attached to) by removing the 2 front bolts and 3 rear bolts. center member and stock mounts drop out as one piece. remove mounts and install new mounts. if using place racing mounts, the rear mount screws need to inserted at a slight angle because the motor is off by about 1/8". put new mount and center member piece back on car. don't tighten the bolts all the way, u might need some play to line up the mount thru bolts. tighten thru bolts and tighten center member and ur done.
if u have a hotshot header, the pipe will be in the way. but u can work around it. after the install, the car will shake some at idle because the mounts are more solid than stock but it should stop shaking after the mounts settle down/loosen up a little (about 2 weeks). hope this helps.
I had to have mine done by a shop cuz I couldn't loosen 3 of the bolts on the crossmember...I had a pipe on the wrench for leverage and everything...and I'm a big dude. I so desparately want a set of air tools.
I went through 2 sets of stock mounts in 50K miles. I will not be getting another set of cheap Nissan mounts again. Place Racing will be the only way I go. And I couldn't get it off the crossmember either. Had to take it to Nissan both times. This time I'm going to a local shop because they both charge the same price 100 bucks.
Just get the Place Racing ones. I like them. My car shakes like champ also with the a/c on. When you first put them in it's real bad, but they break in after a while. When I first put mine in I hated how much my car shook, but it does get better. Peace