Yeah, true Jimmy. But even on Tino's car I just can't bring myself to use Bunnings spec bolts. It's even hard to find (sometimes impossible) socket head capscrews in anything but UNC/UNF and coarse metric. None of which suit Japanese cars.
These guys are supplying high end gear, it's not cheap. It should come with a complete fitting kit and a set of instructions would be good so you don't have to trial fit, cut, weld, grind, trial fit again, repeat etc.

Edit; And while I'm ranting, see that fancy diff cover? Tino asked them to airfreight two of them (one for me) and fit them both in one box to save freight. Sounds simple enough? No, they were each in a box as big as a shoe box, then those two inside a box the size of a dishwasher! We airfreighted about a cubic metre of packaging, cost more than the parts.