The details can be found in the UDFRequestTypeAccess table. You can use SQL Profiler to trace the user interface action to obtain the required information.

For example, you have a configurable field "RequestText485" and you want to know what request types were selected for it. You can use the following script to trace UI action to get further information:

SELECT ut.*, t.Description FROM UDFRequestTypeAccess ut
INNER JOIN RequestType t ON ut.RequestType = t.Code
WHERE Field='RequestText485'