Correcting wrong values in price layers after tickets have been sold

We have a situation where the price layers from some tickets have been set up with incorrect values and tickets have been sold before this was discovered.  The face value of the tickets remains the same, but the way this has been divided across price layers is incorrect.

I am looking into whether it is possible to correct this in orders sold with the incorrect price layers.  It looks to me like it could be done by:

• Upading due_amt & paid_amt for relevant rows in T_SLI_DETAIL
• Updating relevant rows in T_TRANSACTION
• Updating relevant rows in T_PAYMENT
• Updating T_GL_POSTING_FTP to divde money correctly across affected gl_account_no's
• Updating T_GL_POSTING_HISTORY to divde money correctly across affected gl_account_no's

Is there anything that I am missing?  Am I crazy to even contemplate attempting such an adjustment?