Advice on main/rod measurements + undersize 1

[PhilBeans]

As part of my E30 refresh, I measured the crankshaft rod and main journals (88 325i, 329,000+km, average of 3 readings taken with a decent Mitutoyo digi caliper):

Main1: 59.961
Main2: 59.960
Main3: 59.963
Main4: 59.960
Main5: 59.963
Main6: 59.963
Main7: 59.960

Rod1: 44.959
Rod2: 44.954
Rod3: 44.959
Rod4: 44.953
Rod5: 44.954
Rod6: 44.952

Assuming I'm reading the numbers right, both Bentley and BMW TIS are telling me the rod and mains are outside of "standard"

So, I'm guessing I need to go undersize 1 on both. Is there anything I need to be mindful of when getting this kind of work done? The journal diameters for undersize 1 look pretty damned specific. Has anyone here had crankshaft undersize 1 (or 2) work done?

Should I forget it and just start looking for a replacement crank? Also, is "nitriding" essential when getting M20 crankshafts undersized?

[daimlerman]

When I built my 2.7,some 5 or 6 years back now,the engine machining place told me the crank would require grinding undersize.
They told me that the degree of undersize would be more dictated by the availability of oversize bearings than by the minimum amount removed from the crank.
Engine has now run getting on for 50k miles with no oil burning,no pressure loss and minimal loss to drips.I do not need to add oil between services,level drops about a quarter of the difference between full and low on the stick.

So I would seek advice from whoever you have selected to do your machine work,there's plenty of 'meat' to go at!

Cannot help regarding 'nitriding',sorry.