[Morgester]

Since it is a federal offense to alter a VIN and state title as legally issued by another state, why is it that California's DMV does so on a regular basis when it comes to these "legally titled and registered" automobiles?
(I am not talking about a car using Titles Unlimited or any other service such as that one).

California asks under penalty of perjury what year the vehicle was manufactured. We can all agree that the vehicle was not manufactured in 1965. This not a question of honoring a vehicle title from another state (your welcome to visit and drive your out-of-state vehicle here) but rather complying with California law once you choose to register your vehicle here. Just because another state allows a vehicle to be registered doesn' mean that California has to allow that same vehicle to be registered.

2: Why is it that California is the only state in the nation to force the retitling (a change in title, year, make, model, or otherwise any change to another states legal document) and recertification of a new California VIN when a federal mandate and law has already supplied both of these items?

Ask the kit car manufactures if the are a vehicle manufacture for federal VIN purposes. Don't confuse federal requirements (or really lack thereof) with State registration. At issue is when you choose to bring a car to California as a California resident and drive it, you must comply with California law.