You can get new rubber plugs in packs from most hardware/ auto shops. Don't be put off by dirty originals, if you can find them, hot soapy water, a scrub, then a coat of protectant will bring them up like new...... for the heater seal get a 1m x 1m x 5mm sheet of rubber from bunnings, about 20 bucks, should be enough to cut out that, aswell as new drop tank straps and the splash guards for the front wings......
Hey Flighter, the cars painted, head over for a look anytime

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Cheers Drew......