You’ll have to go back to the person that told you it would work on your Classic, after all that is your source for converting your Classic to a Frankenbow. I would think there are a lot of technical factors/hurdles to get over.
Personally, I think whoever told you that was having some fun at your expense. The PSE DNA cam system is not a solocam for starters, so there is not 1:1 replacement/fit. The DNA cam system was designed for a split limb bow with beyond parallel limbs … read very high limb preloading. Your classic was not designed with high limb preloading, so the Classic limb deflection will probably be way too weak, maybe lucky to get your Mathews Classic rated DW minus about 15 to 25 lbs. Also the DNA cams are very large, so it is doubtful the Classic limb forks will accommodate them … after all, that is why the DNA is put on a split limb system. You’d have to figure out the string and cable lengths. Once you have the string and cable lengths worked out for a decent BH, the bow ATA won’t be the same, the DL won’t be the same as what is set on the DNA cam … typically, because of the A-T-A difference and limb deflection differences, you’d end up with a much longer DL, like 5″ longer than marked on the DNA cam. Finally, and most disappointingly, you won’t get the DNA cam speed out of it … you’d be lucky to get 10 fps more than what the Classic is rated, very possible less speed than what the Classic solocam is rated (310 IBO).
A good number of forum members are wishing for a long-ATA bow with 7″ BH, solocam, with decent speed. Your Classic comes pretty close to that. If you want the DNA IBO speed of 340+ fps, I’d recommend the ChillR and the Classic as the backup bow.