P1 is used in N5,N6,N7,R5,R6,R7,R60 up to and including 1989, R70 up to and including 1989. Some pilot P3s may have been in 1989 or prior machines. Small P3 is used in R40,R50,R42,R52. large P3 is used in 1990 and newer R60s, 1990 and newer R70s,R62,R72. R62 and R72s are basically fat R50s where most every thing is wider with the simplicity of the R50s. My question would be what are the P4s going to beIJIJIJ