I would STILL have the deck height on that block measured! Especially when every single book I have says that the 71-73 D2AE-BA blocks are 9.480. Every reference I found on the net confirms this. Not saying they couldn't be wrong, but it's better safe than sorry. the only references I found that claimed 71-74 blocks were 9.503 are forums just like this. VERY unreliable source!
DEfinitely get that deck height measured properly before you start ordering parts!