2005 CRF450 Valving question

I purchased a 2005 CRF450 used in the fall. The suspension (valving and springs) was set up for a 150 lb "B" rider by Facorty Connection.

I am a 200 lb "B" rider.

Can I get away with just changing the springs or would the valving need to be changed too?

I keep going back and forth between-

A. Sending it back to them and paying around $600 to have it set up for me

B. Putting the stock rear spring in and .49's in the front. (That is what I hear everyone is doing)

C. Putting the stock springs in and going from there.

Any opinions?

OK... you answered the EXACT question I had. Thank you... I really appreciate it!

I am not afraid to admit that I know nothing about valving.

Now my next question.....

If I go to Race Tech's site and enter my information about spring rates it says to use the stock springs basically.

I read in MXA that the hot setup is run .49's in the front and lower the oil volume.

What is your take?

I have the stock springs... but would not mind buying some new one if it is worth it....