6.49% sounds good to me... the only time I tried getting financing for a collector car (about 6 years ago) my bank quoted me 12% (or was it 15%?) when they were offering new-car loans at a much lower rate; shocked (I'm a home owner with a great financial record), I backed off in a hurry, and the car sold before I had a chance to look around for other financing.
I doubt you could do much better than 6.49%, because even 30-year home mortgages are approaching that range, which might be another way to finance: if you are a home owner with some equity and a mortgage at or above today's interest rates, you might think about refinancing the mortgage to pull just enough money out of equity to finance the car... the mortgage is tax-deductible.