In the USA Chevrolet Master Parts catalogs,
3835499 is listed as a 235 and also a 261.

That head casting number was used twice and has 2 different part numbers.

For the 261, in 1954, the part# 3703569
and also the 1950-52 235, part# 3835545

I'd be a little careful about the Hemmings head casting info site. In addition to 3835499, it contains other errors.
Example, 1955 truck with a 216, also 1954 truck 3635499 with a 261(should be 3835499)
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The 1950 Master Parts Catalog listing for cylinder head:

1941-49 ALL (use 14 MM spark plugs) casting 3835409, part# 3835408
1950 ALL w/ 216 Eng. casting 3835517, part# 3835543
1950 ALL w/ 235 Eng. casting 3835499, part# 3835545

The 1951 Master Parts Catalog listing for cylinder head:

1941-49 ALL,
1950-51 ALL w/ 216 Eng. casting 3835517, part# 3835543
Note: When 3835543 is used for replacement on 1941-49 it will also be necessary to use 45 degree valves.

1950-51 ALL w/ 235 Eng. casting 3835499, part# 3835545
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The 216 casting 3835517 is listed until 1953.
The 235 casting 3835499 part# 3835545 was later changed to part# 3835908. Listed as 1950-52 ALL w/ 235.


-Tom

1950 Chevy 3100 w/ 1956 235