So I did the 4 piston brake swap on my 91 coupe and stuck with the single piston brake lines since I read on a thread that they work fine. I screwed them in but the nut part of the line is sticking out a bit and doesn't make contact with the caliper. Will this be an issue?

 

Shouldnt as long as it doesn't leak. The nut isn't what seals the line, but rather the pressure it applies to the flare on the end of the line.

 

Take a pic to explain what you are talking about.
I am sure I went through this before and used a couple extra copper crush washers..

 

Here's a picture.

 

YUP ..that's it.
The flex line is meant for the other caliper so it is too deep.(the caliper too shallow to allow the line to fully thread in)
The copper crush washers will take up the room inbetween the caliper and the line nut.

OR you can just bite the bullet and get new flex lines.

 

Or you could machine the ends short enough for the crush washer to seat.

 

Doh, I was thinking hard lines.

Ignore my post.

 

I actually have a set of hardlines, but one appears to be bent out of shape. Which is why I stuck to the single piston lines