PeopleSoft to Oracle Fusion. Rate of Effort Benchmark

Hi Everyone - I am currently consulting to a company who are upgrading from PeopleSoft to Oracle Fusion. The company has 3000 employees, and is looking to install its Finance, HCM, SCM, Guided Learning, Security (Breakglass, Vault, VPN) and Procurement modules. I am in the process of evaluating the system integrator responses and the variation in the rate of effort (contractor days) that the various responses are proposing is enormous. I have spoken with Gartner, Oracle and a range of others, there is a plethora of cost comparison data, but no one can provide the number of 'working days' required to undertake the work. Yes, I hear you all saying it depends on the scope of work, but what if we just look at installing the modules in a greenfield site without any complications such as integration into other systems and change management/training etc. Any thoughts or knowledge of benchmarks? Cheers Alan