I don't know for certain, but it does appear that the final drive ratios are different between the EX vs. DX. The DX manual had a 4.11 final drive while the EX came with a 4.41. The DX used 185/70R-14 tires while the EX used 185/65R-15 tires so I'm not sure off the top how the actual rolling diameter compares. Short of finding somebody that has done the swap and is willing to share, you may be best off just going in and eyeballing, measuring and comparing if you have access to both cars. If nobody out there knows or is willing to share, you may have to start digging through technical specs, and try looking in Honda shop manuals or even Wikipedia for things like VTEC engine physical characteristics vs. the regular Civic engine. Also look and compare the transaxle gasket where it mates to the engine block. Both the DX & EX share the same front & rear track width so that is promising. Doing a dry run via Honda service manuals first would be tidier than sliding underneath and twisting wrenches.