Hey guys. I know the t56 is about 2 inches longer than the t5. If I install a t56 in my IROC will a 4th gen aluminum driveshaft bolt right in? Essentially what I am asking is the 4th gen driveshaft roughly two inches shorter than a 3rd gen driveshaft...

Thanks!

 

A stock 4th gen T56 and bellhousing are the same length as the 3rd gen T5 and bell.

There are other setups that vary in length especially adapter plates and scattershields.

 

O ok so it is just the shifter location that is about 2 inches further than the t5 shifter location?

 

correct

 

Two inches further back than the t5 correct, and is it recommended to use a 4th gen aluminium one? rather than the steel 3rd gen one, what are the pros and cons, I know 4th gens can snap their stock driveshafts off the showroom floor, but it would only be goin in a 305 tbi for me..

 

Yes, you'll just have to expand the T-5 shifter hole but I'd wait until the trans is in to cut so you don't cut too much.
An aluminum driveshaft is lighter so it'll require less power to spin which is a benefit. For a 305 tbi, you'll want to free up as much power as possible so I'd recommend the aluminum.
I've seen some stock aluminums fail on mild cars, and some hold up behind pretty stout power plants, really depends on suspension, tires and a little luck. Steel is stronger (chromoly is stronger yet) if you're going to be pounding on it hard and running slicks but for a street car with the 305, I think a stock aluminum will suit you fine.