What I really like about these drawings is how comprehensive they are. The A2/2 drawing for example has drawings for 4 of the 6 locos in this class alone, with all the main variations. I use them a lot in my model making. They are especially good for scratch building as you get seperate side views of the mainframes.
I take it this P1 is for MSTS?. I have also been working on a P1 loco but this is for Trainz. havn't done much work on it of late as i've been concentrating on updating my Rebuilt Merchant Navy and working on a GCR 8k. Again these are all for Trainz. Anyway good luck, P1 is a favourite class of mine.