Magnum V belt conversion

So just fitted the spacer my friend made for the crank pulley and it fits perfect, checked with belt alignment tool and its spot on in line with the pump pulley so for a total of $60 i now have new aluminum crank and water pump pulleys so on to the alternator, thanks to the pics sent i now have an idea of how its mounted so need to make a bracket and spacers.
Can anyone confirm the belt measurement as in height and width ??? The only V belts i have are from a British 6 cylinder and they look small on the pulley.