kyles got it right on this. the early hilux only came with standard cab. Main option was short or long bed.

The 20R and 22R carbs arn't exactly the best and do require some work. I'm going to replace mine soon with some sidedrafts. I bet you your Acelerator pump is going or gone. More than likely the sub diaphram went byebye on you. Basically it's pumping in too much fuel when you initially gas it which causes teh engine to stumble.