K75 spark plugs/wires

[Motorhobo]

One of the OEM spark plug wires on my 95K75 failed. I replaced it with an aftermarket silicon wire from BeemerBoneyard  - http://www.beemerboneyard.com/12121459876csn.html. I left the other two OEM wires in there. I didn't change the plugs. Now I'm reading up on plugs and see two NGK matches for K75: NGK DR7EA resistor, D7EA non-resistor. There's this comment on a BMWMOA post:

Personally I don't think it's a great idea to mix gap and resistance, IMHO more likely to have fouling problems on the K75 - which is already noted for this.

My 94 K75 has the original OEM spark plug wires. Thinking of switching to the aftermarket silicon from BB. So --

1) Does anyone know if the silicone replacement plugs from BB are resistive or spark-gap?
2) Is it a bad idea to mix them or should I replace the whole set? I've been running the one silicone with the two OEMs for a couple thousand miles, nothing's blown up yet.
3) Which NGK plug (resistor or non-resistor) should be used with the OEM and silicone aftermarket plugs respectively?

I don't know jack about the electricals -- time to learn, this seems a good place to start.

Thanks -- Van

[wmax351]

1) I'm not sure. I think they are likely resistive, the spark gap ones are a pain to deal with. From what I can tell from the picture, they are standard wires with NGK sockets on the end. As far as I know, those are only available in resistance or non-resistance.
2) I wouldn't mix them. You are creating a differential environment between your cylinders. If one went bad, the others are probably on their way out. The spark wires are a known weak spot on the K75.
3) I would go with the non-resistor, since you likely have resistance caps.