Hi Duco,
I've been working on building the car, it's a huge amount of work, making everything from scratch. Had to relocate the supercharger because it was hitting the hood side. As for the alternator, I purchased a small 12v off of ebay, trimmed off the ears, built the case by slitting a 5" diameter tube, squeezing the tube to about 4 1/2" if I remember correctly and welded the seam. I used the original end bells from the generator and extended and adapted the shaft to use the original pulley and fan. I don't think cooling will be an issue or at least I hope not. I wish I could be more helpful. I have attached a few pictures.
Thanks
Pat