Dual Contracts - What should happen ?

If, after the SFA and SPL get their act together and start investigating the alleged dual contracts situation, Rangers are found guilty of not registering their players correctly, what sanction should be taken against them.

Bear in mind the following,

1. There are many precedents regarding action taken against teams who have played unregistered players (automatic loss of game) bear the following in mind.
2. We know that Rangers are not in a position to repay any prize money they have been paid over the said period.
3. Rangers have 'Won' many titles over the period, titles that have given them the opportunity to be invited to play in European competitions.

In light of the above should they be

1. Stripped of all titles/cups they have won over the period ?
2. Relegated to the lowest division or remain in the SPL ?
3. Be banned from competing in European competition for a period ?

What recourse do/should the teams who were wronged have if the SFA/SPL are found to have been lax in the upholding of their rules. Are the SPL/SFA in a position to compensate any clubs ?

This issue alone, if proved, would mean that any club that has come up against Rangers over the period would have a axe to grind in terms of lost revenue, lost opportunity to participate further in competitions where Rangers were the cause of their demise etc.