I used the "Live Chat" on Summits website and here's what they said to a question I asked.

Chad: Hi, my name is Chad. How may I help you?

Mike Frade: I've got an old Shelby Ram Box intake and I'm trying to find a dizzy that'll fit. If I order one and it doesn't fit, can I return it and try a different one?

Chad: Hi Mike, As long as the item is new and unused, we will accept the return 90 days from the date of purchase.

Mike Frade: So inserting it into the block to test fitment is acceptable?

Chad: Yes, that is fine, as long as it doesn't get scratched up.

Mike Frade: Great! I guess it's time to go shopping! :-)

Chad: Ok, have a good day!

So after Roger gets me some measurements.. we'll order one in.. or maybe two... 8-)