Yes, you can "link" an Excel spreadsheet to PRO/Engineer and keep that as a separate document external to the model.
As soon as your assembly has any INPUT parameters, you will have the option to "Read File" when you regenerate your model.
So create these three INPUT parameters in your assembly
INPUT
MY_PARAMETER_NAME_1 NUMBER
MY_PARAMETER_NAME_2 YES_NO
MY_PARAMETER_NAME_3 STRING
END INPUT
Next, create a text-file:
MY_PARAMETER_NAME_1 = 500
MY_PARAMETER_NAME_2 = YES
MY_PARAMETER_NAME_3 = "SOME TEXT"
Save this text-file as: "c:\temp\input.txt"
Regenerate your assembly, choose Read File, and enter "c:\temp\input.txt"
Check the values of your INPUT parameters, they should be like the values from the text-file.
From Excel:
If you want to do this from Excel, you must write a simple marco which creates the "input.txt" file. In our case, we create an OUTPUT workheet which holds three columns. Columns A holds the NAME of the parameter, column B holds the equal sign ("="), column C holds the actual value. The macro must combine those three columns to a text-line and write it to the "input.txt" file.
Within PRO/E: Create a mapkey which will execute these steps: Edit --> Regenerate --> Read File --> "c:\temp\input.txt"
You can also create a button which will execute that mapkey.
HTH!
