Manx Norton carb stud spacing

I was wondering if any of you lucky Manx owners out there could tell me the distance between the studs (center to center) that mount the carb spacer to the head. Trying to identify a random spacer that I have.
Thanks
Jeff

2 & 1/2".

Depends on the year of your manx, of course.
2" was earlier.

Thanks Rohan.
I have a sort of fancy looking cast aluminum spacer with fins around it. It measures 2 1/2" on center between the stud holes. I just wasn't sure what it was for, and I'm not lucky enough to have a Manx to measure. Appreciate the info.

Finned spacers sound like an accessory fitting - or perhaps something off a Goldie or Velo or compy Matchy or Enfield ?
They used the same sized big carbs, on later models ?

It's definitely an aftermarket type piece of kit. Likely not even for a Manx Norton. It definitely looks more BSA or Velocette related, but I'm no expert on either of those. I suppose my question was more aimed to see if it would indeed fit the spacing of a Manx. I have no actual use for it, but it's easier for me to hang onto it if I know that it could fit something that I one day, hope to own. Otherwise it's merely a paperweight.