I have a 76 monte carlo.I would like to replace the steering box due to being hit.What other gear boxs from other cars found at a wrecking yard would fit with no mods.

Robert most GM boxes can be used with the following caveats:

- 2 different input shaft sizes/spline count. make sure the repacement matches yours or take the lower portion of the steering shaft with the new box

- flare or oring style hose connection. Yours should be the flare type. You can use the oring type if you also pull the pump off the donor car. most metrics and 80 or later cars use the oring style.

- different cars (camaro, monte, metric) use different pitman arms on the output shaft. I have changed arms from box to box with no problems in the past but not sure it is the same from your box to the metric oring type box.

- several ratios are out there. Camaros and Transams are most likely to have the fast ratio boxes but is no garrantee to have fast box.

I have a few boxes on hand if you want one.one or two are the z-28s also have pumps with both style fittings.I ran a malibu last year and have lots of parts I want to get rid of.  
        Roy Guy  661-889-8589