Guage wiring--Again

[Palf70Step]

I know this has been killed alot around here but I have a confusion question. Picked up a factory guage /bezel panel to use in my truck to replace the idiot lite one. Been reviewing what's needed.

1. need to rewire the connector for the changes
2. need a different temp sender

Things I didn't find and are not sure of

1. is the oil pressure sensor the same for both idiot light & gauge or do I need to swap it out also.

2. My truck is a 70 and the guage panel came out of a 68. I noticed that if you went to buy a new dash harness they list the 67-68 as one item and the 69-72 as another item. What, if anything, is the difference and is this going to cause a problem.

My engine is the 250 I6 if that makes any difference

Thanks