Painless Harness 60217...

I am finally getting started on my '64 stepside project. I have a '00 5.3L with the attached 4L60E that I'll be installing. I just received my Painless Wiring Harness (P/N 60217) and will be sending in my ECM to get reflashed. On the ECM Reflash Program Information Sheet they provide, it asks some questions I don't know the answer to and hopefully someone here will. It asks for:

1. Cooling Fan #1 and #2 ON and OFF Temperature
2. Speed Limiter MPH
3. RPM Limiter
4. Idle RPM
5. List the codes or description of codes I would lke turned off

If anyone can help me with these questions, I would appreciate it.

Most of that can be answered by the tuner based on your modifications.
We ask similar questions, http://www.nelsonperformance.com/form.htm
the temps are based on your stat rating, the rpm limiter based on the vehicle specs and engine mods, speedo is removed and idle based on cam profile.
Since it's a conversion, i wouldn't think any emissions need to remain.

Probably a dumb question, but just thought about it last night as I was cleaning up the engine getting it ready for the install. If I already have the original ECM and wiring harness, do I need to have an aftermarket wiring harness? That would free up a lot of cash to go towards other items that need attention.

You can rewire the factory harness you have, or we can rework it for you, cost is $450.