400 with TF 240 heads - valley plate options?

I think if you are willing to spend time instead of $$$, you could experiment with a stock valley pan to open up the ports to match the Trickflows. For me, I just did not want to spend the time. It did not look like they would require a lot of trimming, but depending on what tools you have, it might be a pain in the butt trying to keep the area flat while still sealing. Stamping and laser cutting would be the way to go- but not for a slight trim job!