I'm converting from 2-BBL to 4. I have everything but the carb spacer and am unable to figure it out. Was the spacer the same from all 4-BBL cars? Does anyone know the correct part number for the spacer. I've seen spacers on e-bay and they'll say 289 and Hipo. Is the difference the pistons and heads only for the hipo compared to the non-hipo.