Possible to update a revenue extension

Summary:

Client wants to use the percent spent revenue extension. We are able to use the cost and revenue forecast to calculate the percent spent percentage. But we need the revenue amount to be based on the latest approved revenue forecast amount. The existing extension uses the project contract funding amount. Is it possible to change the extension to do this?

Note the client reviews the project forecast on a regular basis, so the project forecast cost and revenue amounts can change regularly.

Content (please ensure you mask any confidential information):

Client wants to use the percent spent revenue extension. We are able to use the cost and revenue forecast to calculate the percent spent percentage. But we need the revenue amount to be based on the latest approved revenue forecast amount. The existing extension uses the project contract funding amount. Is it possible to change the extension to do this?