rb25/26 transmission wiring in s14 questions?

[driftunit1]

I have a few questions about trans harness wiring in my s14 rb26 with rb25 transmission.

#1 for the oil sending unit , the stock 240sx one will swap with the 26 so i don't have to change the connector , but will it be right since the 26 unit looks like it is restricted compared to the 240sx unit..

#2 I need to hook up my rb25 speed sensor which I know I have to cut off my factory s14 connector , but which color wires go on either side off the 25 speedo plug since it is labeled + & - really small on the 25 speedo connector.

#3 I read a thred about using a 300zx na speed sensor with the rb25 red gear on it to get the right signal for mph. is this true?

Any help with any of these questions would be appreciated.