mx5cartalk.com

Hi, I am unable to help you with the brake question, but if your car was built in 1990, it will have 'pop-up' headlamps and is an NA. The engine capacity will determine weather it is an NA6 or an NA8 (1.6 litre/ 1.8 litre). NC's are the current model and were built from the mid 2000's. Let people know where you are, there are streams of owners groups all with a wealth of practical experience.
Welcome to the obsession.
Enjoy. Greg.

1990 model will be an NA6.

These will fix your rear brake rattles: http://www.mx5parts.co.uk/brake-fitting-rear-p-958.html
You need two sets, one per side.