I need a radio for my 1983 toyata collara.:)

Your info is a little lacking but I think that most front mount radios should fit, I recommend an adaptor harness to go from your radio harness (straight wires) the original cars harness plug (connector). If a hack job was previously done on your car and the original harness plug has been cut off then you need to change one wire at a time while installing your new radio unless an experienced person is doing the work then they should at least make some notes as to which wire is which.

I work on Toyotas in Japan and they do not require a mounting kit, the radio does need brackets on each side, I would think that if your radio is original that these brackets are installed right now but be prepared for another expense of a bracket kit on top of the adaptor harness.

If your new radio harness comes with a harness that does not have the little male and female connectors on each wire then you will need these items and a special pair of wire crimpers also.

Everything I am saying assumes you want to upgrade from your old original radio to an up to date AM/FM/CD or something, or do you want an original Toyota radio that matches yours?