Bernie if you do have Strombergs I can back up what George says. I have found the plastic floats in them prone to leaking manifested by fuel dribbling out the trumpets. I have changed 3 of them over the last 10 years or so. My car would start missing at idle due to the rich condition. XK's Unlimited now makes a solid plastic float that seems to solve it. If you get them be careful. I had one where one of the float pods would wiggle around on the metal support piece and when installed would drag on the brass plug so I had to pull it back out and get a new one.
David Barnes
68 E-Type FHC