As a recent trend, there are increasing opportunities to use "Cactus Fusion", a front tire for 4wd, for the front tire of 2wd. (Yokomo part number (YAU-6855), Honest part number (U6855)). By changing to Cactus Fusion, the feeling of ground contact will be further improved and you will be able to bend well, so please try it.
However, if you simply replace the tires, the overall width will not meet the JMRCA regulations, so you need to make some ingenuity.
By using J-concept or Associate front wheels, the wheels will be about 1mm narrower than Yokomo wheels. (The front inner is not used)
Also, by replacing the outer bearing of the front knuckle with a thin bearing, it becomes narrower by 1 mm on each side. (AXON BM-LF-007, etc.)
When fixing the axle, insert a shim with an inner diameter of 5 mm and a thickness of 1mm to adjust. (Square SGE-7510, etc.)
By applying these, you can use Cactus Fusion because you can have a margin of about 2mm according to the JMRCA regulations!