I was wanting to know if swapping in a 9in is worth it. I can pick up one for 50$ and a guy told me he would weld every thing on to make it fit foa around 100. My ? is i'm going to put a LT1 in so should i swap it or just leave it alone???

 

Yes, its worth it, if you are making the power to warrant a 9". If you buy a $50.00 rear, and pay $100.00 to have it welded up to fit a third gen, I would be worried about the safety of the unit. If you you will find the pros and cons of undertaking this mod. A 9" is a DEAL for $50.00. You might want to just upgrade your existing rear, if the LT1 will remain stock, or almost stock.

BTW, I paid $2400.00 for my currie 9', complete. there are no free lunches. Beware!

 

Welding on the spring mounts, shock mounts, panhard mount and LCA mounts is the easy part.

Is the diff the same width as a third gen? Is the welder willing to fabricate a torque arm mount? I highly doubt that. What brakes are on the diff or will you need to fabricate something to use Chev brakes? Ford wheel bolt patterns are not the same as Chev. Your factory wheels will not fit. Is the bolt pattern even a Ford car pattern or is it the large truck pattern? Is the axle size 28 or 31 spine? Is it an open carrier or a LS diff? Is the gear ratio worth using?

If you have to change everything to make it work, $50 isn't a good deal.

As mentioned above, there is no free lunch.

Personally, I'd say drive what you have until it breaks then consider how much to invest in a better diff.