I have a build thread on here from when I did my 4.0 with prices and pix.
I did aftermarket heads,porting,Comp Cam,pushrods,rockers,etc....but didnt do a tuner or headers yet and I can tell you it hauls *** now. My truck is an auto trans and with the big cam its a little soft off idle but when it hits 2800-3000 rpm its like I opened a nitrous bottle!
I have been putting my built up Bronco2 on my 1500lb trailer and pulled it all summer with my Ranger and it pulls everything just as easy as my fathers 01 F-150 4x4 5.4
1983 Ranger 5.0,9in,d44,37" Iroks
1988 Ranger 2.3t