auto to 4 spd OD swap

I'm looking for information on installing a manual 4spd OD into a 65 Barracuda. The current transmission is a 904 atuo that is has a high pitch whine from front pump area.

Stock 273 with 2 bbl GM TBI system 2.73 rear end and 14 rims.

Looking for best fuel mileage and the least amount of problems down the road.

I'm not wanting to drag race.

I'm looking at a Hydraulic clutch system.

What clutch dia should I look for?

The donor car should be a Aspen or Volare for a short tail shaft is that correct?

What bell housing do I need to find?

What improvements should I do to the Al trans?

I know that drive shaft must be modified.