The output jack is on the side in those PB-30Ms, so you don't need to make an extra hole if you modify the pearloid scratchplate you've got (well it should be on the side, but I know someone got a kit without a side hole drilled for them). You just need to cut the scratchplate plate down to fit.

You probably need to mess about with some tracing paper. First mark out the shape of the body and the existing pickup and control rout. Then lay the new pickguard on top and mark it's outline (including screw and control holes). Make sure you get the position/angle correct, so use the neck pocket outline as a guide. You should then be able to see how well the two match up, and what you can cut off the pickguard to make it fit the PB-30M body.

I use a thin bladed jigsaw to cut out pickguard blanks to almost the correct shape, then sand back to the outline you want (I now have a bobbin sander to do this but you can file and hand sand). You can then bevel the edges with a file and sand smooth.

Remember that the pots are wider than the control holes, so you may need to widen the rout to accommodate the pots being in a place determined by the pickguard. If you've got a router, then use that. If not, a sanding drum on a Dremel tool works well. Or you could even chisel it out It doesn't have to be super-neat as it's hidden. You only need to enlarge where the pot goes so it will fit. Just make sure you mark the pickguard outline on the body before doing any work to ensure you don't enlarge beyond the pickguard outline.