Connecting diesel heater into OEM rear heater

[MWADE]

Hi all, I've got an unconverted bongo (rear heater works just fine at the minute), I'm about to install a diesel heater (under passenger seat as usual). However, I'm a little reluctant to mount the outlet in the step area as I think it'll take a good kicking from my haphazard children as they go in and out.. What i was considering was routing the heater outlet across to the drivers side (in the engine compartment) and coming out into the rear OEM heater "well".. from there i was imagining either tapping into the outputs (so the new heat comes out of the high level rear vents and the low level vent), or even tapping into the inlet of the heater matrix so i can use the fans/direction control of the matrix to control the new heat source..

A couple of things that have crossed my mind so far..
1) losing heat in the engine bay due to a longer run.. maybe some insulation will help, or just turn it up a bit..
2) I might have to power the rear heater from the leisure battery to enable use when engine not running, no real issue.
3) Maybe have to reduce pipe size slightly to ease the route across from passenger to drivers side?
4) I've no idea what issues I'll find getting a route from the engine bay into the heater matrix well - I've not taken the side panel off yet, just been going off videos/pictures on the internet.

Has anyone done this kind of stealth install already? Generally, has anyone got any thoughts/issues/concerns with my "plan"?

Many thanks!

[g8dhe]

I believe one person has written about putting the entire diesel heater in place of the original rear heater, but not sure about outcome!
The existing plastic air piping is not designed for very hot air which comes out of some of the diesel heaters, you may have problems, suggest you might want to check this before installing the entire system. I doubt that you would be able to use the original fan and system it is a closed unit with very little spare space, probably best to remove the unit and then just use the plastic piping if its suitable to handle the higher temperatures mentioned above.

[MWADE]

Thanks Geoff, good thought about the higher temp and the limits of the OEM plastic.. maybe i need to mock the heater up in the garage to appreaciate the heat it'll produce (I might be under-calling it in my head!). Also taking the side panel off should probably be my first move, so I can see what I'm working with..