yeah its called checlerplate and a sheet steel bender a la every other kingswood ute.....seriously a bodykit for an 82 celica?? you could try one from a Dodge Omni or something like that - they look kinda similar.....try an '84 Sigma GSR kit and then cut and shut it to fit.
if you want a spoiler for the trunk try an ae82 seca rear spoiler....