RE: Time for something else...
Man that battery size really makes things hard...
Kyosho laser ZX5, I suspect with battery straps and some clever thinking they might fit
Tamiya TRF 201 XR, might fit???
Do u have a SCT?
AE SC10, or similar converted into a rally car?
Last idea.... Use all 3 for a 9s conversion on a 1/5 scaler?