Rab...
my advice is if your not confident then do not do it...
will end up costing more in the long run...
not knocking you mate as i wouldnt attempt it either..
thats what this site is bad for....people saying this is a piece of piss and thats is easy to do...
its obviously not....
will you be confivdent running big boost thru a head gasket fitted by yourself?
build it once and build it proper...best way