Rear-end weight difference

Thanks, guys! So more 60 lbs., huh? Ewww.

I'll trust you more experienced guys that it won't hurt perfomance much, but I'm looking at gas mileage, too (and hoping the the benefits to city mileage even-up the highway loss with the 3.23's). Any other ideas where I could make up some of that weight? I know the T-5 weighs 75 lbs, but that doesn't include the custom bellhousing (maybe 10 lbs? haven't weighed it), and I've heard my 904 is around 102 lbs.

An aluminum center section is cost prohibitive. How many pounds could I save by going to an aluminum driveshaft? I'll need a new one (or get mine shortened) with the rear swap anyway...

Probably worrying about this too much. Thanks for your patience! :)