What do i need to know to replace factory radio with aftermarket radio.
How to remove the radio and how to wire it up. www.crutchfield.com is a good resourse for aftermarket headunits, speakers and installation kits with all instructions.
Also the Astra has a European head unit so if you plan on using the radio at all you'll need to get a connector adaptor for the antenna as it uses a small square connector instead of the typical large male plug in type found on most antenna cables. I believe it's BMW style connector, any car audio installation shop should be able to get it for you even Best Buy. I just had to deal with the for my XM direct connect antenna adaptor for factory head unit.
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