Posi Unit question

[johnny79]

Looking for a posi unit to throw in the Cutlass and I'm searching jegs and summit and they tell me that I need a 7 5/8" unit. I know I have a 7.5 from my build sheet codes:
GH2 & 2AH

RPO           |--------Axle Code--------|
Ring Gear   Code   Ratio   Conventional   Limited Slip
-------------------------------------------------------
  7.5       G72    2.14       2AK            2BK   (aluminum brake drums)
  7.5       GH2    2.29       2AH            2BH
  7.5       GU1    2.41     2AJ,2AZ        2BJ,2BZ
  7.5       GM8    2.56       2AA            2BA
  7.5       GU2    2.73     2AB,2AX        2BB,2BX
  7.5       GU4    3.08     2AC,2AV        2BC,2BV
  7.5       GU5    3.23       2AD            2BD
  7.625     GT4    3.73       2TF            2TH   (Monte Carlo SS)
  8.5       GU6    3.42       3TP            3TJ   (T-Type, GN Std.)
  8.5       GT4    3.73     3TG,3TE        3TR,3TX (442, GN Opt.)

  8.5       GU2    2.73       8YB            8YP   (B-Body)
  8.5       GU4    3.08       8YD            8YR   (B-Body)
  8.5       GU5    3.23       8YE            8YS   (B-Body)

So what's the deal? Know of what unit I should get? I know I need 26 spline. Are they interchangeable?
http://www.jegs.com/i/Auburn+Gear/109/542044/10002/-1

 

[pontiacgp]

a 7 5/8 carrier fits in a 7.5 housing.

 

[johnny79]

And no problem with the axles?

 

[pontiacgp]

nope....the 7 5/8 carriers can be found in Camaros and some were 28 spline and others were the 26 spline so you just have to use the axles that match the carrier. If you are going to use 26 spline you may want to consider aftermarket axles since the axles are the weakest link

 

[johnny79]

If I need to get aftermarket axles, should I just move to 28 spline and get a totally different posi unit? What would you recommend?

 

[chevyman454]

just get a A-body rear from a 70-72 they fit just fine 🙂

 

[JBreu]

just get a A-body rear from a 70-72 they fit just fine 🙂

Actually '66-'72 will all fit 🙂

 

[pontiacgp]

A body 68 and up had a rear end 4.5" wider than what is on a G body....

 

[beermonkey9417]

just goto strange engineering,http://www.strangeengineering.net/ or call them, there really helpful and know what they sell. plus, there right here in morton grove il.

 

[JBreu]

A body 68 and up had a rear end 4.5" wider than what is on a G body....

Look at my car and pics---------rear is from a '69 Chevelle. I think it looks just fine🙂