The differences depend on the part. Some parts, like the latch, underwent several changes; other parts remained the same. The hammer stud nut is the same for all models and for the .38's as well (check the GPC Item number).
Note that what looks like a sideplate screw is not a screw. It is a nut that fits down over the hammer stud to hold the sideplate on. The hammer stud may be broken but there is no "screw".
Gun Parts Corp (www.gunpartscorp.com
) shows parts for those guns; if you give them the model as I gave it to you and the serial number, they should be able to find the right part.