Alignment of Gen.1 sub-frame

[RamAir]

So, I have mounted the AFX-spindles on my Firebird -68 and I will take the car to a shop for adjusting the camber/caster/toe-in.
I have checked the alignment of the sub-frame and it is about 5-10 mm (1/4-3/8") off according to the spec.
How close to the spec. do I need to adjust the sub-frame. Any one who have a rule of thumb for this?

M

[exwestracer]

Really depends on where you took that measurement... If it's 3/8 off at the balljoints, that could have an impact on alignment. 3/8 at the core support isn't really anything to worry about, IMO.

Also, are you measuring to the rear unibody holes, or the ends of the rear axle?

[RamAir]

I have measured according to the blueprint from the manufacturing. I have checked the straightness and distans between the front and rear master gauge hole (located close to the front attachment point of the leaf spring). My car has 4-link, so I will also check the straigtness of the rear end and if it is off I will adjust the control arms.

[exwestracer]

I'd be most concerned about rear axle ends to ball joints. Get the wheelbase right, then cross measure from axle flange wheel registers to opposite ball joint. If you have to move the links more than about a 1/4", you've got a problem...