I didn't hear you mention about the transmission, are you using the v6 one for the v8 or did you use something else? Getting there, looks like the factory put that in, good job.
Both the v6 and the v8 use a 4l60e but the v6 uses a different bellhousing and input shaft. So yes the v8 transmission is similar but different. The V8 uses the same bellhousing pattern as a small or big block chev.
hang on a minute, did you take the remaining A/C gas out of the system ebfore rmeoving the engine? sorry didn't watch the whole video but I own and love the VS cars myself