T&D has a free inspection process. You pay freight roundtrip. We take everything apart, then inspect, measure and advise. After millions of cycles, aluminum goes beyond its useful life.
In the case of your rockers, they may only need to have a few bearings replaced. But, they may need to be rebodied, while using the old bearings, axles, tips, etc. It all depends on their use, abuse, age, etc. Or, possibly you over-revved and put a valve into a piston. It is possible that just one or two rocker bodies might need to be replaced.
If you suspect anything, even the age of your rocker system, return them for a full inspection. It is best to let the sales department know that your rockers are headed this way but not a requirement. Make sure to enclose pertinent information and just what you want done. Again, it is a free service from T&D.