If only I had a garden path (link for explanation)

I have done the machining bit of my modification, and at first thought the block was square on the milling machine bed. Machined 5mm off one side, turned block around to do the other side, started to mill off the metal but the 2mm cut one end was nothing at the other. Realigned the block and all was looking good until I decided to put the end bearing cap in place to measure step down to plate. On the side I did first it measured 5mm cut from where I left metal by starter mount (to be cut off) but 6mm at the bearing cap. luckily I decided to use 3mm steel plate (not the 5.5mm ally), so I can now go up 1mm to 4mm plate. If only i had a garden path i could have used the spaggy method, and it would probably have been square / flat. Also not necessary but I machined off part of flywheel housing where it mates to adapter plate which is still 5.5mm ally