IIRC, the 1.88 needs to have the bore notched for valve clearance.
Valve shrouding is something you should worry about. Other manufactures don't worry about it. While it is true you'll make more power with I shrouded valves, you have bigger fish to slay first.
The piston is one such item. If you plan on making use of the stock slug, you may have a problem. Reason being is lack of on the shelf slugs to start. Second, if you you have them custom made, it cod cost a grand to have them made since it'll be a one off slug.
Machining the stock slug down to make a zero deck height slug will also require that the valve reliefs be cut. That 318_349 stroker threads shows how it is done. Not to my liking. But ....... It gets done. The one bad point I did t get thrilled about was valve lift is limited due to shallow valve reliefs.
