Rear seats

[Kevin Crisp]

Hi, new to this forum.  
I am looking to install rear seats in 2015 enterprise van. I am having rear windows fitted over xmas but want to look at installing foldable rear seats.
So far my plans are fit bracing plate behind side pillars for seat belts. fit bracing bar under floor above tank to take seat rails/belts, removing floor and bulkhead and sound proofing/carpet. removing ladder rack style metal work behind drivers seat and installing that and another behind new seat positions, then bracing roof channel to take front seat belt mount. Fitting new seats with heater pads controlled locally.
This is all well and good but;
is tank easy to lower,
can I support front seat belt from roof structure,,
is there a 8amp plus supply in rear of van for heater pads (towbar connection ?),
was planning on using C4 picasso rear seats bolted thro floor/bracing,
will use high tensile bolts etc as done this conversion of my camper and can weld anything extra if reqd.

Has anyone done this. dont want fold and slide rear crew seats as carry occasional long lengths and lose front seat length.