Fine control of plot

I'm trying to create a graph where I could plot some lines on the right side. Here an example:
layout(matrix(c(1,2), 1, 2, byrow = TRUE), widths=c(6,2), heights=c(1,1))
x = 1:100y = rnorm(x)+xplot(x,y)
reg = lm(y~x)abline(reg, col = "red")
plot(1, type="n", axes=F, xlab="", ylab="", xlim = c(-1,1), ylim = c(min(y), max(x)))segments(-0.25,min(reg$fitted.values),0.25,min(reg$fitted.values))segments(-0.25,max(reg$fitted.values),0.25,max(reg$fitted.values))segments(0,min(reg$fitted.values),0,max(reg$fitted.values))

However, I cant figure out how to make it a bit nicer by removing extra space to the right.