Haven't read everything on this thread,
All I know is I insured my green 94 300tdi 90 with flux. Sold it paid a increase to insure my track car, sold that got a quote for another tdi 90 but a 97 reg they wanted to put my premium up again, I argued and got told it was newer so it's not the same, argued and they agreed with a manager if I bought one same age same engine they would but my premium back to the start of the policy, few weeks later I bought a 94 tdi and they kept to there word,