found a T5... got some questions

[19GMC63]

I'm going from a SM465 to the 5-speed, so everything is pretty much straightfoward. I'll use my 4spd bellhousing so I'll keep my mechanical clutch. A new 10.4" clutch kit is on it's way to adapt the 26 spline input shaft. So my questions go out back to the output shaft.

I can't use my current yoke correct? I've found that T5's are 27 spline, but I can't find what SM465s are. If not, what yokes will work?

As far as driveshaft goes, what should I do there? I know it has to be shortened quite a bit (actually I'm gonna get a new one made) I just don't know what style u-joints it's using now. All I know is the rear end is a 10 bolt out of a 80s 1/2 ton.