Hello Kevin,
Some of the high-level questions to consider that would come to mind are:
1) Why do you want to integrate your CRM with Eloqua?
2) What information does have to flow- back and forth, between CRM and Eloqua?
3) Timing: How often does this information need to go back and forth
4) Since your CRM system doesn't have native integration support with Eloqua, API would become essential here. Your team needs to think how to utilize Eloqua API to send and get data from Eloqua. Do you need to send activity data? Contact Data? do you need to write data to CDOs?
5) determine which system will be the gold source of data if previous data exists.
6) Apply the integration in a gradual process in which you begin with essential components and then extend it based on what you see from the initial integration results.
Thanks,
Tarek