Yes, the ALT PCBa is compatible with all of the ALT cases, low or high profile, anodized or ceramic coated.
Since you have a Drop branded ALT, you don't need a new diffuser either, just the case itself.
Novice here, does this keyboard come built? If not, does it contain all the required parts for assembly? Want to make sure that I'm buying a fully functioning keyboard and not just a "part"...
Why does the MXRSKEY CK650 65% that was not Drop, had a Battery capacity: 8,000 mAh & this MXRSKEY CK820 75% layout only shows a 3,000 mAh Battery Capacity?