For virtually any O.E. carburetor from about 1925 to 1974 try the following:

(1) bring up your favorite search engine (I use Google)
(2) key in the number as well as thecarburetorshop

Example 2193495 thecarburetorshop

(3) This will normally bring you to a page on our website, go to that page
(4) Use the "find on this page" command (under "edit" if using Microsoft I.E) and key in the number
(5) This should take you to the exact application, in this case a GMC 270.

We have almost 100,000 entries listed on the website; and it is there for all to use.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop