Tire rubbing issues
 

I currently have occasional tire rubbing issues with my current setup.
I have ridler wheels, 18 ×8 up front with 4.5 bs and 245 45 18 tire. In back it's 18 ×9.5 with 5.5 bs and a 295 45 18 tire. Should I go with 40 series tires or reduce section width ? This is on a 1970 Buick GS without mini tubs.

Where and when is it rubbing exactly? Also how bad?

The fronts are rubbing in the center at the top ehere the inner fender bolts to the fender. I just realized that the rear is only on the passenger side. There's more space on the driver's side. I'm guessing my rear diff. Needs to go to the left a bit.

I have the exact same set up in the front, 18 ×8 up front with 4.5 bs and 245 45 18 tires and don't have any issues with rubbing.

Replace the 3 (I think, 10-2 o’clock position on the inner fender on both sides) inner fender bolts with 5/16-18 3/4” long Allen head bolts. Should fix the rubbing up front. You can buy them at most hardware stores.

I completely removed the bolt in the area it rubs on

I should probably also mention that up front I'm using stock spindles with tall ball joints and BMR 2" lowering springs.

Check your front end alignment. Some negative camber will make a big difference.

Don

What control arms are you running?
Dhutton is right. I had the same issue on my 66 Chevelle and when I added tall ball joints to my Hotchkis upper/lower control arm setup I was finally able to get enough camber to keep my front wheels from rubbing the insides of the fenders.
Also, if you added front disc brakes that adds width and needs to be compensated for.