ID the block

[zicc1835]

these are the numbers stamped on the pad on the front of the block I can't get a camera in to see casting numbers Power Glide kick down bracket is in my way ...im searching .....this is a 69 c-10 half ton and the glide is original and on the SPID I didn't and can't get any info from the PO or the PO before him someone did a recent resto that's just OK .... the heads are interesting and what's got me wondering 327 ....69s came with IL6 307 350s not sure or is this a early 69 with a leftover 327 ??? or a 350 that's been upgraded some what ?

PS in my younger days if you had the number stamps you could put any Id# you wanted on that pad