kz1000p rear tire size query

So I swapped the forks on my kz1000 csr for kz1000p forks and now realize that I need the front police wheel to fit the rotors on. While I'm at it i might as well put a police rear wheel on too, right? Wouldn't the stock 3.00x16 rear wheel combined with the police 2.15x18 wheel could cause poor handling? Im kinda scared of poor handling now.... IYKYK

Now my question; for the rear police wheel (2.50x18) would it be too much to fit a 130 tire on? I hear that its possible that the tire could deform to fit the smaller wheel. Im asking because it is difficult to find matching tire sets for the stock police wheels.

If having the 16" wheel on wouldnt cause poor handling, I won't worry about it, but I am currently worried about it.

My opinion is that the stock rear wheel would be fine (and definitely better than squeezing a fat tyre on a narrow rim which would cause sidewall flex and probably make the bike weave) with the 18 front as long as you swopped the trees with the forks

I did swap the trees also. The lower triple was cooked so I almost had no choice.  Now I just have to figure out headlight accommodations. Well sounds to me like I'll be keeping the 16" rear wheel for now unless someone else has something to add.