Join our CAD community forums where over 25,000 users interact to solve day to day problems and share ideas. We encourage you to visit, invite you to participate and look forward to your input and opinions. Acrobat 3D, AutoCAD, Catia, Inventor, IronCAD, Creo, Pro/ENGINEER, Solid Edge, SolidWorks, and others.
The way I do it is by creating a new folder and putting the drawing file and the part file (of a different but similar part) into it. Make sure both files have the same name. Open the drawing file and when it tells you the .slddrw and .sldprt are different from the original select yes as accepting it. Depending on how differently the 2nd model was created will determine how many dimensions and views you will have to repair. I'd make sure you have backup copies of the .slddrw file.
Open your drawing and save as a new name. Close it. Goto the open screen and find your new drawing, but do not open yet. Click on the References button and double-click on the part file name. Find the part you'd like to replace it with on the next file search screen that pops up then OK. Back on the Reference window, select OK. Back on the Open window, click OK.