There is a very good diagram on the Document Downloads section of this site under Technical Documents/Chassis entitled "P-Type chassis clip & Firewall details". It was detailed enough to enable the reconstruction of the firewall on PA1169.
I have a very old one with the face detached, yours if required. Could be usefull as a pattern.
Ian PA 1232
Ian,it would be very useful to see your one to get the position of components correct. Where do you live - I am in Hertfordshire.
Allan
Ian I have looked at the diagram on the download and measured a friend's P type so think I am OK now and don't need your old one. Very many thanks for the offer.