well if my wife was there she would suggest using a double barrelled shotgun to get him out(she hates spiders) what i would do is spray some spider killer on a rag or cloth and set it under your truck and i think for sure the spider would not want to stay near that and would probably come out .i would suggest you take truck outside or be prepared to that the spider will move very fast to get away from the strong smell...just a suggestion
