More early heat exchanger on 3.0 questions

[SCWDP911]

Tried this on another thread, but decided I better start my own...

I just purchased recently, a set of slightly modified early HX's. I want to try a megaphone look exhaust on my 83 3.0 SC. Been reading through a lot of threads on this conversion and have a few questions for clarification:

1. Is there enough benefit gained from ceramic coating vs. VHT paint to warrant the cost? I believe the ceramic is supposed to help keep the heat in the pipe all the way through, correct?

2. Being that I will be putting thin flange HX's on a thick flange car, I am wondering which option would work best:

a) weld on a thick flange to replace the thin (Does anyone have a pattern they can send me for this. Pros and cons of this option.

b) Use some sort of spacer (Copper, etc). Again, can someone tell me the exact length of spacer I would need and best material to use? Should the spacers be the same length for all thick flange SC's, and all exhaust studs?

c) Use the nuts that Brad Brown (vipergrun) found. Does anyone know exactly what size and type of nuts these were?

3. Oil line. I know I will need to replace with an early line IIRC. Is there any other option that works or is this it?

4. Does anyone have a pattern or thread showing how to make megaphones? I was thinking possibly of using a glasspack muffler on each HX, and converting the exit of each into the megaphone. But it is just an idea at this point.

5. Is there a cam that works best with these early HX's on a 3.0?