Info from Nasty Z28 web site...
"VF292800 - is an example of a over the counter crate engine. "2800" is the last 4 digits of the GM part # for the crate engine assembly. The final digit could be a year code.
Another example: A Targetmaster engine (p/n 14009800) built in 1985 could have a code stamped as follows:
A0198005 (A = january, 01, 9800 = pn, 5 = 1985) "
I'd say you are looking at something similar, crate or service engine type of deal for the 350 code.
On the other "F0717D"
"F"- Flint (Motor) Plant....where it was built.
"0717" is date code, MM/YY format, so July 17.
"D" - application suffix - 1958 or 1960 283"....1958 is 170hp, Powerglide trans, 2 barrel used in cars and trucks....1960 is 185hp, Powerglide trans, 2 barrel, used in trucks and cars.
To further ID what you have, since you think it is a 327, is verify the block casting number....283's and 327's do not have the same casting numbers.
If it does have a 327 casting number sequence, then there is the possibility you have a misstamped block, right from the factory.....a not unheard of occurence.
All the digits are stamped in one shot, using a ganged stamp.....since the stamp is put on after the engine is assembled, if the employee assembling the stamp drops one digit and doesn't realize it, or forgets one, and a handful of finished engines get stamped with it before anyone realizes and corrects it they are not going to just toss those engines aside....the assembly line waits for no one.
so get that casting number off the driver side bellhousing flange of the block and post that up. Casting Date copde would help too.