your best bet is to build the stand to the engine thats the way we do them to make sure they are true and also always keep im mind building it to the hull always helps to keep things in tack do to the hull and stringer flexing ive seen them build many times with just demintions and them be close to right but still not perfect
if u want the demintions ill get you some off my boat tomarrow and ill get u a pic of one in process of being built