ModSports is seen on several props. In the PSP version, everywhere ModSports is seen in the PS3 version, it is replaced with ModRacing, which went missing since the beta was showcased at E3.
In pre-rendered cutscenes, you can see Tag's signature on the Red Hand that a certain mod has. However Tag's signature is missing in cutscenes which are not pre-rendered. This presumably means that Tag's signature got wiped off before Richard Short replaced the text with #1 CM.
There is another problem with this, as Tag used a black pen with black ink to write his signature, yet all of the text on the glove is shown as being white. Also, Tag had written it on the tall finger of the glove, yet his text is shown below there.
However, after the Chief recovers from his coma, Tag's Kart is revealed to be visually undamaged from the explosion. This is impossible, because the Chief did not have a copy of Tag's Kart. The funds to replace Tag's Kart might actually be coming from Mother, as she did not sell her paint shop, and there was no mention of it losing income after the ad.
In the PSP version, the Wild Run track's Start Line has a black box where the MRC animation should be. This could suggest that it was built earlier than the other tracks' Start Lines. This could be an error as well, as the rest of the prop looks the same as the official Start Line in the PSP version.
In the PS3 version, this track's Start Line has the normal animation it should have.