There are 2 problems one is that the studs sit too high and will contact the camshaft unless the front 2 and rear 2 studs of each cylinder head are set 2-3mm deeper in the block that means that when you drill out the old threads in the block you need to increase the depth of the hole by 2-3 mm. It should be noted that if you go to far coy could drill into one of the oil lines in the block and you don’t want to do that