Hey Joe.
A P80 is the C70 you have, people wrongly call them a P1 as the second shape V70 (2000-2007) is called a P2 and a third shape V70 (2007 on) is a P3 so people pressume the first V70(and it's C70, S70 and 850 siblings) are P1s. They're not, their chassis name is actually P80.
So, P1 Volvos are the Focus based cars; the 2nd shape S40, the V50, C30 and 2nd shape C70.
Confusing eh, especially regarding the C70 as the later car is an actual P1 chassis and the earlier P80 C70 (like yours) that people wrongly call a P1 :P
Just to show the chassis names ipd's shop is useful 