Originally Posted by skizriz
BJ's off-road actually has Novak kits for about $100 less than Novak does. Go figure.....
That's pretty typical. You'll also find the same thing with Advance. Go to Parts Mike (or any AA retailer) and compare their prices to buying direct from Advance. It's always cheaper for a manufacturer to send to a retailer than to the end customer, so they charge accordingly.
You can swap a Dana 18 guts into a Dana 20 case if it's a large hole D18. Lots of Dana 18 owners have done this after cracking their D18 cases.