The old/new XR3's are interchangeable (the gripstrap widths differ, for the later internal lock), as the hole pattern where the gripframe mates with the cylinder frame is the same.
Where adaption enters the picture, is if the compatibility of the mainspring/lock (or no lock) of the gripframe being attached to the receiving action (lock or no lock types use different MS', & MS or lock support, etc ).
IOW - there's no cut & dried: "X" will drop onto any Ruger, only a strong probability.
I've always had to have the donor parts on hand, to see if/what needed to be fitted (or not). Dang liability lawyers.........