Annual inspections FAA disk, STCs, 337s, and engine changes???Oh My

[DFH65]

So to make this right ifin' I buy the plane. I could get it annualed like it has been for the last 13 years I suppose or to fix it right I need to buy the STC again (already been in touch with the STC owner to see if he has a record of purchase) and then have an A&P (IA?) "install the STC" and file a 337? Is there any time frame or other approval needed?

Then figure out what to do about the polished prop @Tom-D

 

[Tom-D]

So to make this right ifin' I buy the plane. I could get it annualed like it has been for the last 13 years I suppose or to fix it right I need to buy the STC again (already been in touch with the STC owner to see if he has a record of purchase) and then have an A&P (IA?) "install the STC" and file a 337? Is there any time frame or other approval needed?

Then figure out what to do about the polished prop @Tom-D

To get it right, have it annulled, then fix the discrepancies. (yes it is that simple) The IA probably won't even catch the data tag mistake, Polished prop??