I have head of quite a few zip ties doing the trick as well, that is the fuel resistant ones
In regards to the rear exhaust fitting I haven't heard anyone say it would, but there are many that will vouch the dump pipe will..
In regards to your fuel pump questions, if the stagea uses the same pump setup as a R33, we have some genuine Nippon Denso 260L per hour pumps that fit in with barely any changes at all!
In regards to the bosch pumps the 044 is an external pump and the 040 an internal pump..