Only the Team Issue and Team Marin used Prestige tubing, and they were not the same frame design as the lesser models ie. Pine Mountain downwards.
The pre 90 team bikes had a wishbone chainstay set up.
What is odd about your lovely Team frame is that it is not painted, but nickel coated it would seem. But, Marin never stuck firmly to brochures or year model specs. I guess they had an idea in 1990 to nickel coat frames for next line up, and decided to start them earlier. I've had 1995 bikes with 1994 specs in the past!!
It's a 1990 Team Issue made in Marvel. Enjoy.