Yeah that will work. You could probably get one cheaper used off ebay or some other place.

Have you thought about chipping your ECU for retard instead of buying a BTM?

 

There is a MSD 6btm and that one.

the MSD 6btm is the ignition w/ the boost timing master built in.

I have a used BTM which is just the Boost Master Timing, like the one in the picture above for sale. $125 shipped. Includes the original instructions.

If you are interested and don't hear from me. I'll be out of town Monday and Tuesday.