I reality the Flux is pretty stout right out of the box, I would stay away from suspension arms and bumpers, the gear cases and other shiny items may be available from FLM, IRC and a couple other places, reason I say not the arms and bumpers is you want those parts to flex under impacts from...
according to LRP germany you need parts bag 35891, it will contain the parts you are missing.....
https://www.lrp.cc/en/product/various-parts-bag-zr28-32/
A Main is a USA Dealer so I suppose you could contact them to see if they can source your missing parts......
https://www.amainhobbies.com/
That is a good engine in reality, simply a Force engine rebadged for Tamiya, That was built for use in the TNX Race truck now discontinued but Force still has parts available should you need them, if you do decide to replace it I would be interested in picking it up, PM me and we can work a...
Vewy Vewy Carefuwwy..... :)
To be honest you may need to do a bit of trimming on that rounded part of the bulkhead......A dremel with a drum sander on it or a hand file of the half round variety or even fully rounded.....
on my Tiger drive started trucks I am using a drill and a ball ended...
K5.9
High Speed Needle: Flush with groove
Low Speed Needle: Flush with case
Idle: 1 mm
think of the needle faces as a clock face.....
Reset all your needles to baseline and start fresh, make tiny small adjustments (about 1 hour on a clock face) to the high needle only, your idle setting may...
while you have the servo arm off power up the radio system and steer the wheels a couple times while listening for grinding sounds from the servo......
It does look like your charger is an older unit and did come with a balance board for it, but it does just plug in to the side so an aftermarket one should work with it.....
https://www.amainhobbies.com/lrp-zr.32x-.32-spec-4-monster-truck-nitro-engine-lrp32825/p673347
It does say in the literature it is power start capable so maybe a call or e mail to the seller may help you... you are still going to need to purchase additional parts I am sure...... or send it...
https://www.hpisavageforum.com/threads/how-to-heat-cycle-your-engine-for-newbies-pros.6972/
I use the heat cycle method on my engines for the last 15 years or so....
should be able to remove all the sealant with some light scraping, one thing to keep in mind is to lay a bead of sealant and let it set up overnight before assembling the engine, that way you will get a good seal and it does make it a bit easier to remove also..... did you read and follow the...
on another note also consider removing that heavy brass bushing on the end of the crankshaft and just use a short piece of fuel tube instead of that bushing, here is what I did to mine and the bell bearings last longer also......