Ah! You have identified a difference between engines for different markets. In Australia our M103s did not have EGR, avoiding the problem you mention. Having not seen an EGR equipped version I cannot comment on this problem (I have noticed one of the exhaust manifolds has a flat, but no holes cast on the top for the fitment of an EGR valve).
As for reaching the lower inlet manifold bolts, they were not as difficult as they looked. I did it without any special tools. For me, leaving the inlet manifold in place had the advantage of not disturbing any fuel lines, wiring associated with the fuel injection, cruise control or throttle cables, in addition to the greater ease of man-handling the cylinder head mentioned in my earlier post. The manifold stays in place by way of a support attached to the engine block (which you will need to detach to remove the inlet manifold).
Maybe others who have done the head on an M103 (with EGR) could comment.
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.