changing or upgrading to metal wheels

[MasonJar]

The P2K wheels are good. However, as noted above, there are different diameters and different axle lengths, so the true answer is there may be something that is better for your particular application. For example, I am curious to know why you say:

im planning on usng 36 inch metal wheel sets

I would assume from that statement that you are intending to replace plastic 36" wheels, but that may not be the case. If you can tell us a bit more about your particular requirement, someone may be able to make a better recommendation.

Hope that helps.

Andrew