Missing bell housing shim?

Im doing a clutch job right now and the shim that goes between the transmission bell housing and motor(sr20det S-13) got bent and a little messed up. It's causing some fitment issues and I was wondering about the necessity and availability of this part. I can't find anything on the internet regarding the shim, its not mentioned in the service manual and I can't find any replacement ones. I want to know if it will cause any problems to discard it and where I could get one.

I figure with all the lone motors for sale out there that didn't include the shim, there must be thousands of setups out there that dont have it installed but I would like to be certain as I know this can cause drivability problems in other vehicles.

I was able to flattened mine out and reuse it in addtion to ordering a new one for the next time I'm in there. Its part number 30411-52F00 and you can get one at 1stnissanparts.com.