You can fit a Evolva/Delta XP4 first gear, but you need to do some work by yourself in order to fit it correctly.
First, from an old Mugen 1st gear pinion, you need to get the inner lip that separates the 1st from the second gear pinions. This involves serious work with a dremel, because you need to cut it and ground it parallel (this one is just a matter of pure patience.
One time you had the washer, you need to remove the inner lip of the pinion on the Evolva/Delta XP4. This is smaller than the one you need for the Mugen and this separation will be provided by the washer you crafted before. Sorry I do not have photographs now, but on the MRX-4R thread you will find some info when I did this some time ago.
Be advised that a 15 tooth is somewhat extreme for a first gear, roughly this will provide you round 8.1:1 ratio, try first with a 16T who is available easily from Mugen before starting to do this. Could create problems with the second gear meshing or gear selection.
[quote=MugenDrew;2684554]BATTERIES are for FLASH LIGHTS, gasoline is for cleanin parts, alcohol is for me to drink and well NITRO...everybody know thats for racing.[/quote] :D:D:D