Fil d'information

Urban Gardini
Small PE details laying flat against the plastic such as placards and engine grills work with TETC. The PE fuses together with the plastic when it hardens again. But it's not a strong bond but it's an just enough bond.

Martin Oostrom
Use a good primer on the pe. If you can get your hands on it, use a metal primer. This etches the metal so your paint primer sticks better to the metal. Then paint as usual.
If the pe isn't flat to the plastic, superglue (ca) works well, but pva (woodglue) could work too.

Pepe
Looking

Kesa Tiho
@Martin Oostrom does Tamiya primer (Tamiya TA87075, ) work too? Thats all i have

Martin Oostrom
That one is suitable for pe as well.
Be prepared for some frustration. The first time working with pe can be very hard. Cutting the pieces goes very well with an older knife and the piece on something firm, like an old cd. Sand or file the little nibs after cutting and be careful, edges can be sharp.