Although I've never actually seen an M30B30, I'll wager that it will fit GIVEN that the donor motor is the late M30 design, meaning that it has a matching bigger intake. The only difference that I know of between the mid M30 blocks and the late units is in the filter housing: on the earlier blocks, there's an extra hole to accomodate the oil cooler setup. So, there should be no issue on bolting the head to the short block. The question is whether you'll be able to bolt the 3.5 intake on (it should bolt on, but I don't know for certain) and retain the late M30 air flow. Otherwise, you'll have to convert the car to the 530 intake, possibly the exhaust.

best, whit