I've tried to read up a little so I have some info in my head but have always been one that learns better by seeing things in person. So needless to say i'm still somewhat unsure as to what i'm doing,lol.
My situation is that something is wrong with my current 10 bolt. Bearing or bent axle I guess. If i'm going to fix one part I would rather drop $100 and get a kit to rebuild the thing. Prob is its my Daily Driver so I can't have it down for a while and I know very well how projects draw out if you have to constantly stop to learn what your doing and ask questions.
So what i'm considering instead is to just rip another used rear end from a junk yard camaro. The things i'm unsure of are:
1. If I end up with different gearing what is involved in changing a speedo gear. I saw the sticky on how to pick one but didn't see anything about its install and where abouts.
2. Am I limited to just 3rd gen camaros? If I don't want a wider rear end can I just take a tape measure and measure the rear ends or the axle tubes to make sure there the same size. I know the 4th gen is 2 inch wider and don't really want that. If its as simple as measuring the rear end then I can prowl around and find more options(just didn't know if its that simple).

I know my speedo is already off because I have 17s on it. Just didn't want to make it worse and hoped if it wasn't to much of a pain to maybe get it accurate again. I don't really think theres a whole lot to a swap but wanted to have a decent understanding before putting out the money. Don't want to find out halfway in the project I should have gone a different route,lol.
Thanks in advance

 

Forgot to add information. The car is an 87 that came stock with a 305. Hoping to find a rear end that has a posi...

K. Found pretty much everything I need on speedo gear install. Now only really left wondering if I can just grab any 8.5 ten bolt( maybe from under a truck or something) or stick with one from under a 3rd gen camaro...

 

Because of the torque arm mount and the spring perches, you'll be limited to a Camaro or Firebird rear. No other vehicles had the torque arm that I'm aware of.

 

We only wish we could grab an 8.5" from a truck, but it's not possible unless you're willing to do some custom fabrication. An 8.5" does not have the torque arm mount, as mentioned above. And depending on the year of the truck, it will have a 6 lug pattern. I rebuilt my 10 bolt, but if it breaks, I will rip the 8.5" out of a truck and do some custom work to it.