I have noticed several guys redoing or building boats (Finnegan included) that have the jet drive (and intake/shoe) moved quite a bit rearward.  The "cleanout" being outside the boat, rather than inside like mine - which I'm sure is stock.  At one point last fall I was looking at buying a 14-71 blower motor for my boat, but after talking to some experts - or at least guys that know more than me - thewy said I'd need to move the whole jet drive back.  That's more than I want to do, but I wanted to ask why.  There don't seem to be much in the way of tech on such things - even on youtube or here.  What gives?

There are several reasons. One is it makes the boat longer, two to put a racheting disconnect on the drive incase of shut down while at speed, To put a pop off valve on the clean out in case of shut down at speed. It looks cool!