8-3/4 is gonna cost around $1000 to build,more than that if you don't have brake drums and hardware. The a 8-1/4 is fine for cruising. I would get that 8-1/4 and slowly build the 8-3/4 if cost is a issue. Otherwise build the 8-3/4. I personally couldn't afford a 8-3/4 a-body housing (going for...