On the inside of the bar that goes to the upper ball joint there "may" be a casting number. On the right side of my 64-66 V8 spindles, it's visible in three lines, C5DA/3107/B, with the FOMOCO oval. The left hand side is messed up, not legible. On your second picture, the LH side, that area seems to be covered with a sealant. Do some scraping on both.
Jim