Spyderlenscal & teleconverter

[SuzukiGS750EZ]

Hey guys. I have a canon 80d. I just bought a 70-200 f2.8 iii & a canon 100-400 ii. I also have a 1.4x III. I own a spyderlenscal & I'd like to make sure it's sharp with these two lenses but I don't think I have enough room to get far enough away from the target. Can I shoot it close & still get the results I need to adjust?

 

[SuzukiGS750EZ]

My method which I'm sure is wrong is to get everything on the same plane. I then fill the center focus point with the QR code looking block with my grid lines on the 0 line on the target and shoot. Adjust in MA menu, refocus, refocus and shoot. I then move back a ways and shoot from distance seeing if it's all still good. When close and far on same focal length are good I call it complete.