np!
Yeah I'd definitely wouldn't mind the wait to get the aluminum one for sure. Never cared enough about gas mileage on my 240, so I have no comment on that one.
While you're waiting, I'd order a new rear main seal from Nissan for your tranny. It's a good idea to change it out while your down there and while the driveshaft is out. You should also change out the fluid too unless you've done it already in the last year or so.. My recommendation is Motul GEAR 300 75W90 (100% Ester-based Synthetic) if you want the highest quality stuff or Motul MOTYLGEAR 75W90 (SYNTHETIC BLEND) second best stuff for a cheaper price. If either of those are too much bank for you, then whatever you do don't use Redline MT90, that $#!t sucks major a$$. Made my trans notchy when warm and grind 2nd slightly when cold. Could've been just my trans too..