How do you mask body side moldings?

[Steamboat]

I'm trying to replicate a 1:1 car I owned which had white body side moldings. What would you use to mask them before painting?

I have tried using BMF before, but it seems to come off in tiny pieces.  I could also paint the whole model and then scrape the moldings but that seems too labor intensive and has potential for disaster. 

Any suggestions?

[Miatatom]

White Tamiya masking tape? It's pretty thin. I'm saying use it as the molding, not for masking.

Edited January 31, 2023 by Miatatom
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