Moving front spring eyes rearward

RustyRatRod said
The only reason I would ever do that was if the rear axle was crooked side to side.....and then I'd look for the difference to be in a frame rail or the unibody of the car before I even considered moving the spring brackets. I've just never thought it was a good idea. Beside the bad rear shackle angle, it will also pull the drive shaft out of the transmission tail shaft a little.

I have been told that on my very stock 69 car. Never considered it as there are "No" mods at all in axle and drive train location. No vibes while driving.

The front yoke of the drive shaft would seem to be to far out as pictured but pure stock! The longer rear balloon tranny seal is not used. What is the real engagement length required? Any one know what that dimension is?