Hi Bob,
I think the DSC-AGC is simply not meant to be dismantled, and retrofitted with AGC parts (on site). And with the shroud on, it's not suitable for the tasks mentioned. From a manufacturers standpoint that makes sense.
As a user, I'm looking at it the same way as you do. I also would like to know if it is possible to safely turn the DSC-AGC into an AGC if needed/wanted. (Or vice versa if one got the AGC.) As I also suspect they are the same "underneath the hood" so to speak.
But I guess the official answer to that will be, understandably, no.
For the mortar joints I'd say the DSC-AGC with the dust collection shroud will be superior, but obviously you can do it with the AGC, too. I don't think that using any of the two on this type of work would violate any guidelines/rules set out by the manuals.
Kind regards,
Oliver