Wrong Spouses SS# on 2006, 2007 & 2008 tax returns & 401k contributions?

So, using Turbo Tax since creation and rolling everything forward electronically from year to year. Apparently had a typo in Spouse's (who is self employed) SS# rolling into 2006 through 2008, and have used the Tax return as the reference for SS# when opening Simple 401-k, etc. Does this require amending all returns in order to 1) get social security payments posted correctly, and 2) for corrected filing (thus, open to audit starting from date of correction) or is there an easier way that does not toll the statute of limitations for audit purposes?