Am I right thinking it is 4 quarts plus the filter? It is a 73 350. After reinstalling this dipstick tube, the stick is very difficult to install. I dumped the oil, a very short change so I left the filter and put in 4 quarts. I have another stick that fits much better that is the wrong length. I plan marking a mark where it is full.

 

I don't think the filter holds a full quart, at least the short Wix 1258 style doesn't. The 1049 is the tall filter that holds more, which is what I use on my engine, and I put 5 quarts and the oil level is right at the FULL mark on the dip stick. I'd say put in 5 quarts, let it run a bit to fill the filter, shut it down, then put a new mark where the oil level is. You got this.

 

I was thinking the Hastings LF222, same size as the 1258 holds a good 1/2 quart. Yeah maybe another 1/4 to 1/2 quart more.