Your tower looks fine. A FAT shroud does lot require the machining that other 911 shrouds do. Zen went from a Fat 911 shroud to a DTM with no issues. Hell Jake's guys did it. No shims or machining required.
You will have to cut the lug off that the long bolt is sticking thru in you picture. It will hang on the apron when you try to install the engine. You will also have to drill the dimples that the stock breather bail went in. They will then take the bolts (horizontal) that secure and adjust the mounting block inside the breather tower for the DTM alternator stand blots (vertical under alternator).