The 100 series MX manual has the guidelines, and the use of AC43.13 will provide the necessary procedures for this repair. It should not require a field approval providing original Cessna parts are used for the repair. There is a company out of Ohio, Essco, that you can get a 172 manual. Most pilot shops should have a copy of AC 43.13

You are correct... These documents are considered "Acceptable" Data. The maintenance manual used in conjunction with AC43.13 and the use of factory parts, no field approval is needed. This would be considered a MAJOR repair and any IA can sign it off and return it to service. I have done this a number of times and it is quite legal as long as the FAA Form 337 is submitted and the logs are filled out by an appropriately rated mechanic.

Also, concerning the use of AC43.13-1B, a little known fact is that it may me used as not only acceptable data, but also as approved data.
The first page paragraph 1 says in part;

The repair data may also be used as approved data, and the AC chapter, page, and paragraph listed in block 8 of FAA Form 337 when:
a. the user has determined that it is appropriate to the product being repaired;
b. it is directly applicable to the repair being made; and
c. it is not contrary to manufacturers data.

Thanks Del Lehmann, that is how I read the "Purpose" also.  I will continue to pursure yours and Tom's advice.  My FLT SIDS. Inspector is on the field quite often so he roams freely and has his nose in everything!!  Thanks

Have any idea  Airframe overhaul hours for cessna 172 ?