Gary McCoy
I've had the same challenge many times.  I simply finish the project at the original tempo (85 in this case), then speed up the stereo mix to the desired tempo using Time/Pitch Stretch.  Works for me.

Yeah...I've done that...ahem....a few (hundred) times...  ;)  I was just trying to avoid that since the song isn't even done yet.
 
Thank you all again for the feedback.  Whereas, I think we ALL could do without the noise...
 
Happy weekend!!