Sure grip

You should not have to remove it. You can temporarily put the center section in and temporarily install the axels (no gaskets or seals needed for this) be sure you have the backing plates on as well. with one side snugged up the other side should sit flush, if it does not sit flush the you might have a thrust button issue.

Also contacting Cass at Dr. Diff will be a good idea. He is here on FABO but I forgot his handle