SQL Server Developer edition convert from 32 bit to 64 bit.

Hi,

We have microsoft visual studio 2012 ultimate installed on our programmers machines. We also installed SSDT and sql server client tools. Then I and my colleague decided to install SQL Server 2012 Developer edition on our machines so that we can do debugging of our stored procedures. Both of us installed developer edition. but something went wrong in choosing which version I wanted on my machine. When I do

Select @@ version, this is what I get:

Microsoft SQL Server 2012 (SP1) - 11.0.3000.0 (Intel X86)
 Oct 19 2012 13:43:21
 Copyright (c) Microsoft Corporation
 Developer Edition on Windows NT 6.1 <X64> (Build 7601: Service Pack 1) (WOW64)

My colleagues is:

Microsoft SQL Server 2012 (SP1) - 11.0.3000.0 (X64)

                Oct 19 2012 13:38:57

                Copyright (c) Microsoft Corporation

                Developer Edition (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1)

I know that mine is 32 bit developer edition and his is 64 bit edition.

We had to install ODBC DSN for debugging to work. Because mine is 32 bit, it is not working and his works.

My question is:

1. How can I install 64 bit version of developer edition. Can I upgrade.
2. If I can't upgrade, then do I need to uninstall 32 bit developer edition. If yes, does it mess up my rest of SSDT, client tools and visual studio 2012.
3. I am bit hesitant to uninstall, because my work station is needed.
4. What are other alternates.

Please let me know.

I appreciate your response.