The Latchfix product gets good reviews. I ordered the repair kit when the OEM pot metal mechanism from TriMark broke. When the precision machined components in the repair package wouldn't fit, I consulted with the Toolmaker at Latch Fix. He told, an undocumented change to the original lock design was made to correct a flaw in early versions and was never referenced in any nomenclature. Because of the change the repair kit doesn't' fit some early versions of the lock. His explanation included the caveat that incompatibility persists because stale warehouse inventory and the distribution channel was never purged.
The problem is with TRIMARK. The company modifies the product unilaterally without changing the nomenclature. Several versions of the latch exist. Part Numbers are obscure and the risk of getting the old pot metal "nonmagnetic" construction continues. TRIMARK considers their mechanism as "military" grade and boast about their product line being installed on high dollar vehicles around the world. When searching for a replacement, I considered them and contacted Sales Personnel there. As if a salesperson's lack of product knowledge could be disguised as a need for a high degree of technical sophistication being required for a customer to order a doorlatch was an issue, I found their service loathsome.