From what I understand, this is what we'll create:

- client side version of grazcoin/mastercoin-tools (mastercoin-js)
- server architecture for mastercoin block explorer (mastercoin-server)

On the client side, everything is new, and we'll likely borrow liberally from My-Wallet for ideas on how to do tricky things like sign transactions on the client. There isnt really much precedent for this

On the server side, we can shave some time by forking grazcoin/mastercoin-tools and writing some services around those tools, although porting the tools to node would probably be worthwhile IMO. This 
seems pretty straightforward

Does that help?