oil pressure

My 1998 blazer oil pressure is reading 1000 rpm.6 -10 psi, 2000 rpm.around 18 psi
and at 3000 rpm.24-30 psi, is this too low, if so where is the oil pressure sending unit located, i've read that usually that is what goes out.

Thanks

1998 S/T series 4.3L oil pressure sending unit is next to the distributor, and just to the driver side. Before you start replacing parts, perhaps unnecessarily, it's best to check the oil pressure with a manual gauge, (they are far more accurate) just after changing the oil and filter.