HDI rod direction

[Ben]

Right, rebuilding the engine and not too sure which way around I should be fitting the rods. Below is hopefully a picture of a page of the Haynes manual.



Basically the picture on the left shows that XUD rods should be fitted with the shell cuts outs at the front of the engine, and the picture on the right shows that HDI rods should be fitted with the cut outs at the back

Firstly I can't understand why they are different, and I can't really see why it would make any difference as there are no holes or channels in the shells?

But it must be quite important else Peugeot wouldn't have had them opposite ways around.

So do I put the HDI rods in XUD way around, because they are going in an XUD block with XUD pistons?
Or do I put the HDI rods in HDI way around because they are HDI rods?

Help much appreciated because I really want to get this engine built!

Ben