ALRIGHT !!! Heart Attack Attempt #1:
Step 1: Go to Clocking Bell (the fatty fastfood in all San Andreas). Eat till he's 100% fat.
Step 2: Do the marathon: Swim from LS to LV. Run from LV to Mount Chiliad. Bike from Mount Chiliad to LS.
Step 3: If he dont have an heart attack, just explose him with some explosives... lol