Trying to accommodate the rebuilt engine, better head, header, and lockers, I used the "Excellent Condition", on Kelly blue book for my area. Here CA "Excellent Condition" would be $4k and "Good Condition" was around $3200, IIRC. I think your truck is an '89(carb), I used 1990 for the values above.

Take a look at [url=http://www.kbb.com/]http://www.kbb.com/]kellybluebook.com[/url][/url], and see what the value based on a stock truck in your condition for your area. Then add on about $500 for the lockers and performance upgrade, and see what you have. After that check out what other std cab 4x4's are going for in your area/state, craigslist.com will help you there, and then price your truck accordingly.

Given that you are only hoping/needing/wanting to get $3k from it, you shouldn't have a problem selling it. Just make sure that your asking price leaves you with enough haggling room to come way with what you are expecting, a smart buyer will want to offer you less, regardless of what you list it for.