TN1 Visa with no Formal Education but with a Special Skill

For the last 9 years, I have worked for a company that has it's head office in Canada, but a US division as well. They have a custom in-house software that is now being replaced with SAP. Having worked on the original implementation team for this, there are only a few of us that know *both* software programs. We are all in Canada. I have been wanting to move to the US as my boyfriend lives there and am wondering if I can get a TN1 Visa to work in the US under their US division as part of the implementation (which is about 2 years)? I do not have a diploma, but I do have a specialized skill. The company is looking for people in the US to do this implementation but would rather send me than have to train someone on the legacy system. I am currently not under full time employment with them. I Have been doing consulting work for them for the last two years (I was an employee from 2002 - 2007). They would need to offer me a job.

Thanks!

L1 (company transfer) visa sounds right for you. TN would be stretch except for Management consultant category, which is restrictive.