[Spank]

Just set the deafult rep in the options what you want it to be, then set the other options to abnormaly high (unreachable) settings. Eg:

Register Date Factor
For every X number of days, users gain 1 point of reputation-altering power. 9999999

Post Count Factor
For every X number of posts, users gain 1 point of reputation-altering power. 9999999

Reputation Point Factor
For every X points of reputation, users gain 1 point of reputation-altering power. 9999999

Edit: Actually thinking about it, the above probably works if you set the values to 0 to =D