I used an OS46AX with pitts muffler when I built mine. I did not know about the weight at the time, so it remained. I wound up moving the battery to the rear to move the CG back. Had I known about the weight, I would have removed it.

I'd suggest that you take the sucker out. It's dead weight no matter what since it's not even as close to the firewall as possible. It would have been much more effective had they stuck it to the firewall.

How much does your engine weigh? How much does the 46AX weigh?
Don't you think that adding a heavier engine probably would negate the value of that lead?

I just used TOWER's online catalogue to look up the weights of the two engines.
Your engine is roughly 6 ounces heavier than the one I used. If I were you, I'd pull the weight.