Does anyone have suggestions????

Hi, hope there is some good advice for my problem.
2003 ranger 4.0 eng., auto, with O/D, 104,000miles, purchased used with 85,000

Since I purchased this truck my trans would hesitate 4-5 seconds before engaging to drive. Reverse worked fine.
Lately I need to pull shift lever into 1st, low gear and wait a 4-5 seconds to engage, once i start moving I can immediately shift to Drive and all works perfectly until I use Park, then need to start in 1st again.
Today I replaced the trans range sensor with Dorman 511-101 trans range sensor. As best I can tell I have the small tick lined up properly yet now I need to pull shifter lever up tight to left to start engine and still trans does not engage (as stated above)

I guess it was wishful thinking it could be so simple. Am I looking at a rebuild or new torque converter? (I am on the wife and kids budget.)
I checked fluid and level is a bit high but doesnt smell burnt. The truck runs great after you get it moving in low. If I stop for a red light or stop sign and stay in Drive the truck works perfectly pulling out again, the prob is only when you go to park then back to Drive.

I'm afraid I will be left stranded one day soon.
Any and all help is greatly appreciated, thanks in advance
Jake