There is a easy solution!!!
Spiders like a damp dark area to live in.
Remove your top, remove your carpet and put your jeep out in the sun, and angled so that the sun hits your interior. Use a hairdryer and blow it in all of the corners areas that the sun doesn't can't get to.
If you follow the above then your spider problem will be eliminated!
Now the next trick is to keep additional one from getting into it. If you park it into a garage, then have your garage proffesionally exterminated. If you park it outside, then keep the top on and windows up. Have the area that you normally park in outside exterminated.
I have had a lot of experience with getting rid of spiders, because I have lived in Arizona for 39 years and we have a lot of spiders out here, and some of them are very dangerous!!!