Even though the "rules" dictate the past tense, it's quite common to find WOULD in result clauses when the if-clause contains a simple present verb. This is a topic for another posting, however.
The expression "(X) would appreciate it if" is a formulaic way of making a polite request. According to Google, the overwhelming number of verb forms in the clause after this formulaic expression is neither the simple past tense nor the simple present; it's modal expressions with WOULD and COULD. For example,
We would appreciate it if you would answer the following questions, and we assure you that your answers will be held in strict confidence.
We would appreciate it if your office could formally confirm our understanding an this issue.
Other than these verb forms, you find the present-tense modals WILL and CAN, as well as simple present and a few simple past verbs. (My search found very few examples of the simple past used in the if-clause.) Here are some Google examples:
1) Modals CAN and WILL, present tense:
--To assist, I would appreciate it if John will elaborate on his requirements, using the questions I set out below as a basis for discussion.
--I would appreciate it if you can send me the Income Statement and Balance Sheet from year 2000 to 2003.
2) Simple present:
--We would appreciate it if you return this note within 7 days.
--We would appreciate it if she is upfront about the fact that she is on an information mission, ...
--I would appreciate it if you make a link to this web site, and let me know when it is up .
--I would appreciate it if you send me some info on Sambo Jackson.
--I think all of us here would appreciate it if you come back in the near future with feedback on your new venture, ...
3) Simple past:
--We would appreciate it if you told us a little bit about yourself.
--It is an online serial story that is updated weekly with new episodes. I would appreciate it if you checked it out and gave your opinion.
The simple past in the if-clause makes the request more tentative, and therefore more polite, than does the simple present.