Hello everyone. I'm looking to refresh the engine on a 2003 Maxima. My question is what upgrades should I consider doing while I have the engine out? Oh and it has the 6spd manual

 

Don't bother with an old 3.5.

Get a newer engine. Go to http://www.nisformance.com/ for swap info.

 

is there anyone on here that has done them before and can do it for me? Not sure I’m comfortable cutting and grinding on the new engine.

 

Your just grinding down the tabs to utilize the 2003 type of adjustable tensioner, alternator, A/C and P/S...If you can get and entire 09-15 engine with accessories you can do it that way. But custom a/c hoses and P/S will have to be made & auto shops can do that!