Several times during the drive with Doloris, Elvis' body double is clearly visible.
Elvis dives into the inlet and swims across to the diving side. He got out of the water and his hair is combed. He climbs to the top and makes his spectacular dive. He climbs out of the water again and his hair is still combed.
After Mike's fight with the rival lifeguard, the rival lifeguard holds his shoulder and appears to be in great pain and collapses. But after Mike's dive, the rival lifeguard appears with his hand bandaged, claiming Mike has a hard jaw (meaning he broke his hand on Mike's jaw). His shoulder appears to be fine.
Immediately after Mike's high dive his hair is wet in the water, but moments later after climbing up to the landing his hair is perfectly combed.
Shortly before Mike Windgren performs "Marguerita," he is sitting in the balcony having a drink with Raoul and Marguerita, the straw in Mike's glass changes position.
When Elvis and Ursula's characters are at La Perla they order two margaritas. But what they are brought bear no resemblance to the actual drink.