are my front/rear brake lines crossed?

[drdata]

A silly question but my manuals are not clear. On the 78 I just sold it was clear that the MC had a larger front compartment and corresponding brake line. Makes sense as I understand disks need more fluid than drums, hence bigger reservoir and line diameter.

On my new to me 72, which has dodgy brakes, I note that:

1. The MC seems to have the same size reservoir. Is that correct for a front disk/rear drum 72 blazer? It seems to match that shown in the link below.

2. The larger line from the rear MC port goes to the rear drums. The smaller from the front hits a slitter and goes to the front disks. This seems backward, but given the different thread sizes for the two lines it seems unlikely this could happen by accident.

This link has a decent diagram, but has a nice "air gap" such that I cannot use it to confirm which port on the MC/proportioning valve goes to which set of brakes:

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=151

In my case the rear line is larger, and again goes to the back brakes which are drum. The front thinner line feeds the front disks. Is that correct?

Thanks in advance.