Help matching bikes stack and reach

Maybe you guys can help me out

I had a large Speed concept 7.0, no spacers, 100mm stem flipped up (6 degree) and 25mm zipp risers

I am trying to achieve the same stack and reach on my slice 57 (2016)

Trek
Stack 54.1
Reach 42.6

Cannondale
Stack - 54.7
reach - 42

Can I just take a 6 degree stem flipped up and put 25 mm of spacer under it and it should be close?? Just doest feel the same , I feel like all my weight is on my arms. Speed concept felt so good I am thinking of buying an old one just to have that feel back

You can play with this one.

https://app.velogicfit.com/frame-comparison