Need some help here
 

So recently my 96 max has been burning coolant, instant thought is head gasket, im doing an 00vi swap as well and also throwing on some headers, my buddy who is a mech at Nissan helps me do all the work and such, so we were wondering what would be the best route, snag a high mileage 3.0 nd build it up?(pistons, rods, whole shabang) or just swap for a 3.5, my question is tho, what would be the best gen 3.5 to use for this swap and what will i need besides a 6 speed tranny to make it work, thanks in advance for the help!

What made you decide that it is burning coolant?

Have you done a block test to test for exhaust gas in the coolant?

Is there any seepage of anti freeze near the alternator? The water pump lives near there. It will start to seep before it really starts leaking.

Of course you could find a low mileage engine and install that one.

The number 1 question to be answered ...

If all of that time, effort and $$ was planned for the engine you've got, I guess I'm not sure why it wouldn't be worth a little more of each to go ahead and replace the head gaskets ... assuming that's actually your problem of course.

Except that replacing the head gaskets involves removing the timing cover and chains. So would take many hours.
Hours better spent replacing the engine with a lower mileage one.

Every time i start her up theres white smoke coming from my tailpipe, at least till it warms up, its the only thing that makes sense now, i just changed my oil yesterday as well, slightly milkshaked, it wasnt like that in my last oil change but the smoke was coming out the tailpipe, trust me i've done all i can to try nd rule out head gasket as i know how much of a PITA it is

Yup
 

And that is exactly why i never included actually doing the head gasket in my initial post cuz its a PITA, i was just hoping to get some insight on what the better option would be, obviously more gains are in the 3.5 but swaps arent always simple, now building a 3.0 in my garage would be cake nd the swap would be basic, just wanna see how much harder the 3.5 would be nd if its worth the extra cash+ time needed