That engine is overkill, why can he not go with the HPI 18? It should drop right in and he would be able to use the same exhaust.
#1 NTC3 RTR Modded w/JP Racing M12
#2 NTC3 Team Kit w/RB X12
#3 NTC3 FT Kit Ver.2 w/Rody RB V15 Turbo
Savage 4.6SS Kit