I received my Pacenti SL23's recently to go with my Hope Pro3 hubs and have now got the spokes through.
I'm using Roger Musson's wheel building guide as a reference.

First thing is I've noticed according to Roger's book, this rim is a 'type 2' rim which is, according to him, a lot rarer to come across. This is identified via the following method. With the rim placed flat on a surface and finding the valve hole, the hole to the left of it is offset lower then the one to the right of the valve hole.
This is not as easy to see when looking at the holes from the inside of the rim however is clear to see from the outside.

Can anyone else who has used this confirm this?

Stick something through the rim (passing through the inner and outer holes) and look at the angle. The hole in the rim bed may appear to be on the 'wrong' side but the path of the spoke through to the inner edge probably isn't, if you see what I mean. It's very unlikely to be a type 2.

Had another look at it and yes your right, it's a type 1. Confirmed by the staff at Fairwheel bikes.
All built up now, dropping them into my LBS to do the final part tomorrow so should have them back by end of play next week ready for the weekend.