The wiring should be pretty straightforward. In fact I thought all Rangers were pre-wired for a trailer, you just need the pigtail w/ the adapter from your dealer. Even my otherwise very basic '99 XL Sport 4x2 was pre-wired. My dealer did me a 'favor' and threw in the pigtail to sweeten the deal. Although for all I know it was standard equipment.. The LII of course came w/ the tow package..
Unfortunately there doesn't seem to be much you can do to improve your towing capacity. From everything I've seen or read about the GCVR (Gross Combined Vehicle Rating) seems to be the weak point, so lightening your truck would probably help. Carying less crap and people in the truck would free up more weight to tow.
That said I'm pretty sure I exceeded the spec all the time w/ my old truck (the '99 XL Sport). She still ran though. I think the key is to go easy on it, feather the clutch, etc. Also don't do it every day. If you need to tow a lot every day then you need to invest in a super duty..
2003 Ford Ranger FX4 Level II - Silver - Stick - fuelly
2009 VW Jetta SportWagon SEL - Grey - Stick - fuelly
2001 Suzuki Bandit 1200 - Red
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