Rim and Tire Calculator accuracy?
 

So I am looking to replace my TRD wheels and tires and put on my HUffs again.
At least I thought. But I was looking at the tire size I would need to keep the correct height of the tire or as close as I can to the right height. I was comparing my current 235/35/19, and I wanted to go to a 205/45/18 for my Huffs (VW Wheels). According to the calculator the tire heights are within .3 of an inch. 25.5 for the 19 and 25.2 for the 18 inch wheels. Only problem, trying to find a 205/45/18 is next to impossible. But it is the only tire by my estimation that would give me a tiny stretch. Cause as low as I am right now, the HUFFs (on a 225/40/18 tire) rub hard in the rear, but if I had a slightly stretched tire I wouldn't rub as much. I already have rolled fenders and where it rubs is where the lower sections of the fender/bumper meet.
While shopping for tires I found a set of wheels I wouldn't mind buying, but the bolt pattern is 5 x 100 and I could buy a new set of adapters, but then I have to sell both sets of my wheels and the adapters I have now. The set of wheels I was looking at was 18 X 8.5 and +28 offset.
And looking at the tire calculator I noticed the 16 inch factory rims with tires is in 25.3 in tire height. So I am not sure where I wanna be or should be as far as tire height goes, according to that tire calculator.

And while I am here talking about it, should I gauge interest in anyone who would be looking to buy my adapters and HUFFs. The bolt pattern for them are 5 X 112. The rear adapters are 1 inch thick and the front are 3/4in thick.

You could run a 205/40R18.

205/40/18 is too short, it would throw off the speedometer. I am going to figure out how to get the used wheels I saw the other day that are 18 x 8.5 with a +28 offset, with the adapters.

It throws off your speedometer... and? I really don't see the problem.