Saab fuel pressure check valve on XJs?

I'm having the famous rough idle at start-up issue on my '99. I believe it's caused by the leaking of fuel back to the tank after the truck sits awhile. I thought I read on this board or another that someone had installed a Sabb fuel pressure check valve on their fuel rail or some other place. I ran a search but came up dry. Am I crazy or does someone else remember this, too? Thanks!

I believe it was a BMW check valve, try searching for that and see what you come up with.

Thank you! I'll order it today.