oh, maybe i misunderstood your words. Could you tell me how many mm is the inner diameter and outer diameter of the extension tube? So i can start searching for them.
About the chassis...i don't know, i suppose it is the one you mentioned but i had this marder from a guy with an exchange. He took my 1/8 mugen mbx5r buggy and i took his marder so i don't know if it is...seeing your pics it seems to be it.
This marder has:
front elcon aluminium upper and lower XL arms already (i really don't know if i can use them for a stadium model they are very different in shape respect to the stock stadium front arms)
short aluminium front shocks (i will have to change them for the Hummer setup)
a front mechanic disc brake
an elcon drive train unit (just the part for the clutch pinion and layshaft gear) but he cutted the lower differential support part from it

I can't understand why some one has to buy something so expensive and later to ruin it in this way...doh!
It has an elcon differential brake unit, but also here he modified things in a very dirty way....he made a cut (bad cut!!) on the chassis for the brake disc of the differential. Later he should have tought that it was better to put just some spacer under the differential mounts (the stock plastic mounts) to avoid the brake disc from touching the chassis but now there is a bad cut on it damn!
It has 4 ammo (FG red shocks) on the rear end and a Zenoah G2D :blush: with a marder jetpro pipe
Ah...it also have a gear set by elcon, the helicoidal one...unfortunately the layshaft pinion (16T) has 3 teeth broken and i am not able to find an used one on ebay. Maybe i will buy a pinion set from elcon and i will change gear ratio too
I have to change also a lot...well almost all screws because evidently he used what he had in his house at the moment and i don't like this way to do.
Plus i have to buy all the missing pieces needed to transform the marder into an hummer stadium.
At the moment i have no pics, i will take some shots tomorrow and i'll post them. Thanks a lot for your help and sorry for this long polluting post :blush:
Riccardo