Deliverables in multiple git projects

Hi

I have a 5  projects running under 2 agents

All projects are maintained in their own separate git repositories

2 projects are windows based , running  on one of the agents on a windows machine
3 projects are Linux projects running  on the other agent on a Linux machine

All a successfully building  under Teamcity  :-)

I have 2 issue which I need to resolve

Issue 1
The 3 Linux projects need to deliver into single deliverable directory as  follows
  Project 1..  build our Linux system into a directory call rootfs
  Projects 2  builds our Linux tool set and then runs an installation script to install the required files in to rootfs
  Projects 3  builds our Linux applications and then runs an installation script to install the required files in to rootfs

Project 1 deletes the rootfs whenever it builds to ensure no redundant files exist is the deliverables.  Because of this I need to run the installation scripts for projects 2 and 3 on a successful build of project 1.
How do I do this  given they are all contained in separate git repositories.  I.e    How do I reference Teamcity's  mangled  repository names for the relevant installation scripts

                                                                                                                                                     
Issue 2
On the successfully completion of  our test scripts,  I want to label all 5 repositories with a build number .  Is there a convenient way in Teamcity to do this?

Stewart